永别 (yǒngbié) literally combines 永 (yǒng), meaning 'eternal' or 'forever', and 别 (bié), meaning 'to part' or 'farewell'. Together, it expresses a final, irreversible separation — most commonly used when someone has died or when parting is understood to be permanent with no hope of reunion. It carries deep emotional weight and solemnity, often appearing in obituaries, eulogies, farewell letters, or heartfelt spoken farewells.

Unlike casual farewells like 再见 (zàijiàn) or even the more formal 告别 (gàobié), 永别 implies irrevocability and profound loss. It is rarely used in everyday conversation unless referring to death or an absolute, life-altering separation. Because of its gravity, it’s typically avoided in lighthearted or uncertain contexts — using it prematurely or flippantly would sound inappropriate or even ominous.