Meaning

adverb at full speed; with great haste

adverb with all your strength

originBorrowed from Spanish amainar (“to reef a sail (take in part of a sail to adapt its size to the force of the wind); to abate, die down, subside; to ease off, let up; of a person: to calm down, control one’s anger”); further etymology uncertain, probably from a regional Italian (Naples) word (compare Italian ammainare (“to lower or reef (a flag, sail, etc.)”)), from Vulgar Latin *invagīnare (“to…

Etymology from Wiktionary, CC BY-SA 3.0