Abbreviation of about.

Abbreviation of antibody. / Abbreviation of abridgement.

present participle of ab

(idiomatic) A forthright and honest person.

(archaic) A person who remains in bed until late in the day.

plural of lie-abed

(law) From the time when a law, legal right or decree, contract, ownership interest, partnership (etc.) comes into force.

From the beginning.

Antilock brake.

From time immemorial; from an infinitely remote point in the past.