noun
(countable) Something done, a deed.
(obsolete, uncountable) Actuality.
(theology) Something done once and for all, as distinguished from a work.
(law, countable) A product of a legislative body, a statute.
(law, countable) (In the United States) A legislative proposal, a bill that has not yet become law.
The process of doing something.
(countable) A formal or official record of something done.
(countable, drama) A division of a theatrical performance.
(countable) A performer or performers in a show.
(countable) Any organized activity.
(countable) A display of behaviour.
A thesis maintained in public, in some English universities, by a candidate for a degree, or to show the proficiency of a student.
(law) Ellipsis of act of parliament.
verb
(intransitive) To do something.
(obsolete, transitive) To do (something); to perform.
(intransitive) To perform a theatrical role.
(intransitive) Of a play: to be acted out (well or badly).
(intransitive) To behave in a certain manner for an indefinite length of time.
(copulative) To convey an appearance of being.
(intransitive) To do something that causes a change binding on the doer.
(intransitive, construed with on or upon) To have an effect (on).
(transitive) To play (a role).
(transitive) To feign.
(intransitive, law) To carry out work as a legal representative in relation to a particular legal matter.
(intransitive, mathematics, construed with on or upon, of an algebraic structure) To possess an action onto (some other structure). Examples include the group action of a group on a set, the action of a ring on a module by scalar multiplication, and the action of a group or algebra on a vector space via a representation.
(obsolete, transitive) To move to action; to actuate; to animate.
(obsolete, Scotland, transitive) To enact; to decree.
adverb
(text messaging) Clipping of actually.