Saudade (singular) or saudades (plural) (pronounced [sɐ.uˈda.ðɨ] or [sawˈda.ðɨ] in European Portuguese, [sa.uˈda.d(ʒ)ɪ] or [sawˈda.d(ʒ)ɪ] in Brazilian Portuguese and [sawˈda.de] in Galician) is a Portuguese and Galician word for a feeling of nostalgic longing for something or someone that one was fond of and which is lost. It often carries a fatalist tone and a repressed knowledge that the object of longing might really never return.
Saudade has been described as a "vague and constant desire for something that does not and probably cannot exist ... a turning towards the past or towards the future". A stronger form of saudade may be felt towards people and things whose whereabouts are unknown, such as a lost lover, or a family member who has gone missing. It may also be translated as a deep longing or yearning for something which does not exist or is unattainable.
Saudade was once described as "the love that remains" or "the love that stays" after someone is gone. Saudade is the recollection of feelings, experiences, places or events that once brought excitement, pleasure, well-being, which now triggers the senses and makes one live again. It can be described as an emptiness, like someone ( e.g., one's children, parents, sibling, grandparents, friends) or something (e.g., places, pets, things one used to do in childhood, or other activities performed in the past) that should be there in a particular moment is missing, and the individual feels this absence. In Portuguese, 'Tenho Saudades Tuas', translated as 'I have Saudades of you' means 'I miss you', but carries a stronger tone.
The word saudade was used in the Cancioneiro da Ajuda (13th-century), Cancioneiro da Vaticana and by poets of the time of by King Denis of Portugal.  Some specialists say the word may have originated during the Great Portuguese Discoveries, giving meaning to the sadness felt about those who departed on journeys to unknown seas and disappeared in shipwrecks, died in battle, or simply never returned. Those who stayed behind—mostly women and children—suffered deeply in their absence; However, the Portuguese discoveries only started in 1415 and since the word has been found earlier this does not constitute a very good explanation. The Reconquista is also a plausible explanation.
The state of mind has subsequently become a "Portuguese way of life": a constant feeling of absence, the sadness of something that's missing, wishful longing for completeness or wholeness and the yearning for the return of that now gone, a desire for presence as opposed to absence—as it is said in Portuguese, a strong desire to "matar as saudades" (lit. to kill the saudades).
In the latter half of the 20th century, saudade became associated with the feeling of longing for one's homeland, as hundreds of thousands of Portuguese-speaking people left in search of better futures in North America and Western Europe. Besides the implications derived from an emigratory trend from the motherland, historically speaking saudade is the term associated with the decline of Portugal's role in world politics and trade. During the so-called 'Golden Age', synonymous with the era of discoveries, Portugal undeniably rose to the status of a world power, and its monarchy was one of the richest in Europe at the time. But with the rise of competition from other European nations, the country went both colonially and economically into a prolonged period of decay. This period of decline and resignation from the world's cultural stage marked the rise of saudade, aptly described by a sentence of its national anthem - 'Levantai hoje de novo o esplendor de Portugal' (Let us once again lift up the splendour of Portugal).
Saudade (or Saudades) is defined as "a somewhat melancholic feeling of incompleteness. It is related to think back situations of privation due to the absence of someone or something, to move away from a place or thing, or to the absence of a set of particular and desirable experiencies and pleasures once lived". 
Saudade is quite similar to nostalgia, a word that also exists in Portuguese.
In the book In Portugal of 1912, A. F. G Bell writes:
The famous saudade of the Portuguese is a vague and constant desire for something that does not and probably cannot exist, for something other than the present, a turning towards the past or towards the future; not an active discontent or poignant sadness but an indolent dreaming wistfulness.
A stronger form of saudade may be felt towards people and things whose whereabouts are unknown, such as old ways and sayings; a lost lover who is sadly missed; a faraway place where one was raised; loved ones who have died; feelings and stimuli one used to have; and the faded, yet golden memories of youth. Although it relates to feelings of melancholy and fond memories of things/people/days gone by, it can be a rush of sadness coupled with a paradoxical joy derived from acceptance of fate and the hope of recovering or substituting what is lost by something that will either fill in the void or provide consolation.
Although the word is Portuguese in origin, saudade is a universal feeling related to love. It occurs when two people are in love or like each other, but apart from each other. Saudade occurs when we think of a person who we love and we are happy about having that feeling while we are thinking of that person, but he/she is out of reach, making us sad and crushing our hearts. The pain and these mixed feelings are named "saudade". It is also used to refer to the feeling of being far from people one does love, e.g., one's sister, father, grandparents, friends; it can be applied to places or pets one misses, things one used to do in childhood, or other activities performed in the past. What sets saudade apart is that it can be directed to anything that is personal and moving. It can also be felt for unrequited love in that the person misses something he or she never really had, but for which might hope, regardless of the possible futility of said hope.
As with all emotions, saudade has been an inspiration for many songs and compositions. "Sodade" ("saudade" in Cape Verdean Creole) is the title of the Cape Verde singer Cesária Évora's most famous song; French singer Étienne Daho also produced a song of the same name. The Good Son, a 1990 album by Nick Cave and the Bad Seeds, was heavily informed by Cave's mental state at the time, which he has described as saudade. He told journalist Chris Bohn that "when I explained to someone that what I wanted to write about was the memory of things that I thought were lost for me, I was told that the Portuguese word for this feeling was "saudade". It's not nostalgia but something sadder."
The usage of saudade as a theme in Portuguese music goes back to the 16th century, the golden age of Portugal. Saudade, as well as love suffering, is a common theme in many villancicos and cantigas composed by Portuguese authors; for example: "Lágrimas de Saudade" (tears of saudade), which is an anonymous work from the Cancioneiro de Paris. Fado is a Portuguese music style, generally sung by a single person (the fadista) along with a Portuguese guitar. The most popular themes of fado are saudade, nostalgia, jealousy, and short stories of the typical city quarters. Fado, and Saudade are two key and intertwined ideas in Portuguese culture. The word fado comes from Latin fatum meaning "fate" or "destiny". Fado is a musical cultural expression and recognition of this unassailable determinism which compels the resigned yearning of saudade, a bittersweet, existential yearning and hopefulness towards something over which one has no control.
Spanish singer Julio Iglesias, whose father is a Galician, speaks of saudade in his song Un Canto a Galicia (which roughly translates as a song/chant for Galicia). In the song, he passionately uses the phrase to describe a deep and sad longing for his motherland, Galicia. He also has a song titled Morriñas, in which the Galicians are described as having a deeply strong saudade.
The Paragyuan guitarist Agustin Barrios wrote several pieces invoking the feeling of saudade including Choro de Saudade and Preludio Saudade. The term is prominent in Brazilian popular music, including the first bossa nova song, "Chega de Saudade" (No more saudade), written by Tom Jobim. Due to the difficulties of translating the word saudade, the song is often translated to English as No more Blues. In 1919, on returning from two years in Brazil, the French composer Darius Milhaud composed a suite, Saudades Do Brasil, which exemplified the concept of saudade. Saudade (part ii) is also the title of a second flute solo by the band Shpongle, the first one being flute fruit. The singer Amália Rodrigues typified themes of saudade in some of her songs. J-Rock band Porno Graffitti has a song titled "サウダージ”, "Saudaaji" transliterated ("Saudade"). The alternative rock band Love And Rockets has a song 'Saudade' on their album Seventh Dream of Teenage Heaven.
The contemporary Irish folk-rock band The Pogues, have recorded ballads that describe the feeling of saudade shared by many Irish that migrated to America, a good example being "Thousands are Sailing" from the album If I Should Fall from Grace with God
A jazz fusion trio consisting of John Scofield, Jack DeJohnette, and Larry Goldings released an album dedicated to drummer Tony Williams, called "Saudades." Dance music artist Peter Corvaia released a progressive house track entitled "Saudade" on HeadRush Music, a sub-label of Toes in the Sand Recordings. New York City post-rock band Mice Parade released an album entitled Obrigado Saudade in 2004. Chris Rea also recorded a song entitled Saudade as a tribute to Ayrton Senna the Brazilian three-times Formula One world champion killed on the track.There is an ambient/noise/shoegazing band from Portland, OR named Saudade. The rock band Extreme has a Portuguese guitarist Nuno Bettencourt; the influence of his heritage can be seen in the band's album titled Saudades de Rock. During recording, the mission statement was to bring back musicality to the medium. "Nancy Spain", a song by Barney Rush, made famous by an adaptation by Christy Moore is another example of the use of saudade in contemporary Irish music, the chorus of which is:
"No matter where I wander I'm still haunted by your name
The portrait of your beauty stays the same
Standing by the ocean wondering where you've gone
If you'll return again
Where is the ring I gave to Nancy Spain?"
Saudade is also associated with Galicia, where it is used similarly to the word morriña (longingness). Yet, morriña often implies a deeper stage of saudade, a "saudade so strong it can even kill", as the Galician saying goes. Morriña was a term often used by emigrant Galicians when talking about the Galician motherland they had left behind. Although saudade is also a Galician word, the meaning of longing for something that might return is generally associated with morriña. A literary example showing the undestanding of the difference and the use of both words is the song Un canto a Galicia by Julio Iglesias. The word used by Galicians speaking Spanish has spread and became common in all Spain and even accepted by the Academia.
In northern Portugal, morrinha is a regional word to describe sprinkles, while morrinhar means "to sprinkle." (The most common Portuguese equivalents are chuvisco and chuviscar, respectively.) Morrinha is also used in this region for referring to sick animals, for example of sheep dropsy, and occasionally to sick or sad people, often with irony. It is also used in some Brazilian regional dialects for the smell of wet or sick animals. In Goa, India, which was a Portuguese colony until 1961, some Portuguese influences are still retained. A suburb of Margão, Goa's largest city, has a street named "Rua de Saudades." It was aptly named because that very street has the Christian cemetery, the Hindu smarshant (cremation ground) and the Muslim quabrastan (cemetery). Most people living in the city of Margão who pass by this street would agree that the name of the street could not be any other, as they often think fond memories of a friend, loved one, or relative whose remains went past that road. The word 'saudade' takes on a slightly different form in Portuguese-speaking Goan families for whom it implies the once-cherished but never-to-return days of glory of Goa as a prized possession of Portugal, a notion since then made redundant by the irrevocable cultural changes that occurred with the end of the Portuguese regime in these parts. In Cape Verdean Creole there is the word sodadi (also spelled sodade), originated in the Portuguese "saudade" and exactly with the same meaning.
There are other words in other languages which have a similar meaning. Saudade relates to the Italian malinconia, in which one feels an interior satisfaction because it is impossible to find something, but one never stops thinking that one is searching for it. It is an incompleteness that one unconsciously wants to never completely resolve. Saudade relates to the French regret, in which one feels a hard sentiment, meaning hardful, but in nostalgic sense. Saudade relates to the Spanish extrañar, in which one feels a missing part of oneself, which can never be completely filled by the thing you can't have or get back. The word can also be translated by the Spanish expression "echar de menos", which would be roughly an equivalent to the Portuguese one "ter saudades", missing something or someone. The Greek word that comes close to translating saudade is νοσταλγία (nostalgia). Nostalgia also appears in the Portuguese language as in the many of other languages with a Indo-European origin, bearing the same meaning of the Greek word "νοσταλγία". There is yet another word that, like 'saudade', has no immediate translation in English: λαχτάρα (lakhtara). This word encompasses sadness, longing and hope, as does the term saudade.
In Albanian, a direct translation of saudade is the word mall, which encompasses feelings of passionate longing, sadness, and at the same time an undefined laughter from the same source. Other variations which give different nuances to this word are: pëmallim, përmallje, etc.
The Torlak dialect of Serbian has the expression that corresponds more closely to the Japanese and Greek examples below, but can be compared to saudade in a broader sense of longing for the past. It is жал за младос(т) / žal za mlados(t) i.e. "yearning for the bygone"; since the dialect has not been standardised as a written language it has various forms. The term and the concept has been popularised in standard Serbian through short prose and plays by Vranje born fin-de-siècle writer Borisav Stanković.
One translation of "saudade" into Dutch is weemoed; a fuzzy form of nostalgia. In the Romanian language, the word dor bears a close meaning to "saudade". It can also stand for "love" or "desire" having a derivation in the noun dorinţă and the verb dori, both of them being translated usually by "wish" and "to wish". However, although the word dor has a complex meaning, it still does not encompass the full meaning of "saudade". Dor is derived from the Latin dolus ("pain"), the same root as the Portuguese word dor, also meaning "pain". In Welsh, Saudade is said to be the only exact equivalent of the Welsh hiraeth and the Cornish hireth. Esperanto borrows the word directly, changing the spelling to accommodate Esperanto grammar, as saŭdado.
The Finnish language has a word whose meaning corresponds very closely with saudade: kaiho. Kaiho means a state of involuntary solitude in which the subject feels incompleteness and yearns for something unattainable or extremely difficult and tedious to attain. Ironically, the sentiment of kaiho is central to the Finnish tango, in stark contrast to the Argentine tango, which is predominantly sensuous. There is a religious context for kaiho in Finland as well; a sect of herännäiset or körttiläiset more familiarly, has central to their faith a kaiho towards Sion, a unity of faith, and a connection with God, permeating their central book, Siionin Virret (Hymns of Sion). However, saudade does not involve tediousness. Rather, the feeling of saudade accentuates itself: the more one thinks about the loved person or object, the more one feels saudade. The feeling can even be creative, as one strives to fill in what is missing with something else or to recover it altogether.
In Korean, keurium (그리움) is probably closest to saudade. It reflects a yearning for anything that has left a deep impression in the heart - a memory, a place, a person, etc. In Japan, saudade expresses a concept similar to the Japanese word natsukashii. Although commonly translated as "dear, beloved, or sweet," in modern conversational Japanese natsukashii can be used to express a longing for the past. It connotes both happiness for the fondness of that memory and goodness of that time, as well as sadness that it is no longer. It is an adjective for which there is no quite fitting English translation. It can also mean "sentimental," and is a wistful emotion. The character used to write natsukashii can also be read as futokoro 懐 [ふところ] and means "bosom," referring to the depth and intensity of this emotion that can even be experienced as a physical feeling or pang in one's chest~ a broken heart, or a heart feeling moved.
In Armenian, "Saudade" is represented by "կարոտ" (karot) that describes the deep feeling of missing of something or somebody.
The Arabic synonym for Saudade is وجد (Wajd), a state of transparent sadness caused by the memory of a loved one who is not near, it's widely used in ancient Arabic poetry to describe the state of the lover's heart as he or she remembers the long gone love. It's a mixed emotion of sadness for the loss, and happiness for having had loved that person. In Turkish, the feeling of saudade is somewhat similar to hüzün.
In Ithkuil, the root x-ḑ is equivalent to saudade.