Syllable division derived from spelling — this word is not in the pronouncing dictionary, so no phonetic transcription is shown rather than a guessed one.
amain is an adverb meaning "at full speed; with great haste". It carries 2 recorded senses.
at full speed; with great haste
“the children ran down the hill amain”
with all your strength
“he pulled the ropes amain”
Definitions, synonyms and semantic relations for amain come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.