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Synonyms

act on

British  

verb

  1. to regulate one's behaviour in accordance with (advice, information, etc)

  2. to have an effect on (illness, a part of the body, etc)

"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
act on Idioms  

  1. Also, act upon . Conduct oneself in accordance with or as a result of information or another action, as in I will act on my lawyer's advice , or The manager refused to act upon the hotel guest's complaints . [c. 1800]

  2. Influence or affect, as in The baby's fussing acted on the sitter's nerves . [c. 1800]

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

According to findings published in Scientific Reports, galloylquinic acids act on several stages of the viral life cycle.

From Science Daily • May 7, 2026

This is his internal narrative — and he has the power to act on it.

From Salon • Apr. 30, 2026

Tuesday's motion was advisory, meaning cabinet is not legally obliged to act on it.

From BBC • Apr. 21, 2026

You could act on that profitably or just ignore it.

From The Wall Street Journal • Apr. 16, 2026

What happens to a body when a force does act on it is given by Newton’s second law.

From "A Brief History of Time: And Other Essays" by Stephen Hawking

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

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