la·ment / ləˈment/ • n. a passionate expression of grief or sorrow: a song full of lament and sorrow. ∎  a song, piece of music, or poem expressing such emotions. ∎  an expression of regret or disappointment; a complaint: there were constant laments about the conditions of employment.• v. [tr.] mourn (a person's loss or death): he was lamenting the death of his infant daughter. ∎  [intr.] (lament for/over) express one's deep grief about. ∎  express regret or disappointment over something considered unsatisfactory, unreasonable, or unfair: [tr.] she lamented the lack of shops in the town. DERIVATIVES: lam·en·ta·tion / ˌlamənˈtāshən/ n. la·ment·er n.

lament sb. XVI. — L. lāmentum; or f. lament vb. (XVI) — F. lamenter or L. lāmentārī.
So lamentable XV, lamentation XIV.

lament. Piece of elegiac mus. expressing grief, specifically mus. for bagpipes at Scottish clan funerals.