Idioms

Origin of act

1350–1400; Middle English act(e) (< Middle French) < Latin ācta, plural of āctum something done, noun use of past participle of agere to do (āg- past participle stem + -tum neuter past participle suffix); and directly < Latin āctus a doing (āg- + -tus suffix of v. action)
SYNONYMS FOR act
4 record.
6 turn, routine.
10–13 perform, function, work. play. 19, 21 play.
Related forms
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for act up (1 of 4)

act up

verb

(intr, adverb) informal to behave in a troublesome waythe engine began to act up when we were miles from anywhere

British Dictionary definitions for act up (2 of 4)

ACT

1

abbreviation for

Australian Capital Territory
(formerly in Britain) advance corporation tax

British Dictionary definitions for act up (3 of 4)

ACT

2
/ (ækt) /

n acronym for

(in New Zealand) Association of Consumers and Taxpayers: a small political party of the right

British Dictionary definitions for act up (4 of 4)

act

/ (ækt) /

noun


verb

See also act on, act out, act up
Derived Formsactable, adjectiveactability, noun

Word Origin for act

C14: from Latin actus a doing, performance, and actum a thing done, from the past participle of agere to do
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Idioms and Phrases with act up (1 of 2)

act up

1

Misbehave. For example, With an inexperienced rider, this horse always acts up. [c. 1900]


2

Malfunction, as in I'm not sure what's wrong with my car, but the transmission is acting up. In both usages up means “abnormally.”

Idioms and Phrases with act up (2 of 2)

act

In addition to the idioms beginning with act

  • act of faith
  • act of God
  • act on
  • act one's age
  • act out
  • act up
  • act upon

also see:

  • catch in the act
  • clean up (one's act)
  • do a disappearing act
  • get in the act
  • get one's act together
  • hard (tough) act to follow
  • high-wire act
  • in the act of
  • put on an act

The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.