To do with separation; In, into. / To do with time; Each, per, in, on, by. / To do with status; In. / (archaic) To do with position or direction; In, on, at, by, towards, onto.

The ordinal number first, derived from this letter of the English alphabet, called a and written in the Latin script.

(chiefly Scotland) All.

(idiomatic) something that is difficult or impossible to locate; something impossibly complex or intractable

(idiomatic, slang) To make a telephone call. / (slang, with on) To inform, to call the authorities (on).

(idiomatic, US, colloquial) To leave without saying goodbye; leave quietly, run away; scram; depart without taking leave or notifying anyone, often with a connotation of avoiding something unpleasant or shirking responsibility.

Try or attempt (something); to give something a try.

(Britain, euphemistic, idiomatic) To use the toilet.

The lower limit of dating, as of the earliest plausible date at which a fact could have occurred or a document could have been written.

plural of A-side