Swan song

The phrase "swan song" (Ancient Greek: κύκνειον ᾆσμα kýkneion ásma; Latin: carmen cygni) refers to a final gesture, effort, or performance given just before death or retirement. It is metaphorical and refers to an ancient belief that swans sing a beautiful song just before their death while they have been silent (or alternatively not so musical) for most of their lifetime.

The belief, whose basis has been long debated, had become proverbial in ancient Greece by the 3rd century BCE and was reiterated many times in later Western poetry and art. In reality, swans learn a variety of sounds throughout their lifetime; their sounds are more distinguishable during courting rituals, and are not typically correlated with time of death (although see "Ornithological accuracy" below).