A*main" [Pref. a- + main. See 2d Main, n.]
1. With might; with full force; vigorously; violently; exceedingly. They on the hill, which were not yet come to blows, perceiving the fewness of their enemies, came down amain. Milton. That striping giant, ill-bred and scoffing, shouts amain. T. Parker.
2. At full speed; in great haste; also, at once. "They fled amain." Holinshed.