Initialism of Anti-Counterfeiting Trade Agreement.

(law) A thing done between others (such as a contract), which cannot adversely affect the rights of those who are not parties to it.

(grammar) Any of the participants, such as the subject or object, in a grammatical clause.

Able to be acted, as by an actor.

plural of actant

(pharmacology) An anti-inflammatory drug used to treat rheumatoid arthritis.

The condition of being actable

plural of actability

A complex of broad-spectrum antibiotics made by Actinoplanes bacteria.

(zoology) Any sea slug of the family Actaeonidae.