Webster's Revised Unabridged Dictionary · 1913

Damn

Damn (dam) , transitive verb

[Old English damnen dampnen (with excrescent p), Old French damner, dampner, French damner, from Latin damnare, damnatum, to condemn, from damnum damage, a fine, penalty. Compare Condemn, Damage.]

1.
To condemn; to declare guilty; to doom; to adjudge to punishment; to sentence; to censure.
He shall not live; look, with a spot I damn him. — Shakespeare
2.
(Theology) To doom to punishment in the future world; to consign to perdition; to curse.
3.
To condemn as bad or displeasing, by open expression, as by denunciation, hissing, hooting, etc.
You are not so arrant a critic as to damn them [the works of modern poets]... without hearing. — Pope
Damn with faint praise, assent with civil leer, And without sneering teach the rest to sneer. — Pope

Damn is sometimes used interjectionally, imperatively, and intensively.

Damn , intransitive verb

To invoke damnation; to curse.
While I inwardly damn. — Goldsmith