Alternative form of one-on-one

(Internet slang) Used to signify agreement with the comment to which one is replying.

To a high degree.

A selective service class denoting that the registrant is available for service in the military

(US, colloquial) First class, superior.

Alternative form of A1

(sports, skateboarding, snowboarding, skiing) Clipping of 180. (180° spin)

The number one (1). / (Internet slang, leetspeak, sarcastic) Deliberate misspelling of !, imitating someone who is too excited to consistently press the shift key while typing exclamation marks.

Alternative spelling of A1

Alternative form of plus one