(archaic, literary) With all of one's might; mightily; forcefully, violently. / (archaic) At full speed; also, in great haste. / (Britain, dialectal) Out of control. / (obsolete) Exceedingly; overmuch.

(nautical) To lower (the sail of a ship, particularly the topsail). / (figuratively) To decrease or reduce (something). / (intransitive, nautical) To lower the topsail in token of surrender; to yield.

Obsolete spelling of amain

simple past tense and past participle of amain

present participle of amain