From Latin 'languere' (to be listless), from PIE *sleh1g- (to be slack) — same root as Germanic 'slack.'
Lacking energy or vitality; slow and relaxed; weak or faint from illness or fatigue.
From Latin languidus (faint, weak, weary), from languere (to be faint, to be weary, to be listless), from PIE *sleh1g- (to be slack, to be languid). The same PIE root produced English slack, lax, relax, and languish, all sharing the core idea of something loosened, loosely hanging, or released from tension. The Latin languere carried connotations of physical illness, erotic weakness, and
The English word 'slack' and the Latin-derived 'languid' descend from the same PIE root *sleh₁g- (to be loose, to be weak). The Germanic branch preserved the 's' (slack); the Latin branch lost it (languēre). A languid afternoon and a slack rope share the same etymological DNA — both lack tension