noun

1. mental suffering caused by loss, disappointment, etc.; sadness, grief, or regret
2. that which produces such suffering; trouble, loss, affliction, etc.
3. the outward expression of such suffering; mourning; lamentation
4. earnest repentance; contrition sorrow for sin

Etymology: ME sorwe < OE sorg, akin to Ger sorge < IE base *swergh-, to worry, be ill > Sans sūrkṣati, he worries about, Lith sergù, to be sick

intransitive verb