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Synonyms

assert

American  
[uh-surt] / əˈsɜrt /

verb (used with object)

  1. to state with assurance, confidence, or force; state strongly or positively; affirm; aver.

    He asserted his innocence of the crime.

    Synonyms:
    maintain, avow, asseverate
    Antonyms:
    deny
  2. to maintain or defend (claims, rights, etc.).

    Synonyms:
    support, uphold
  3. to state as having existence; affirm; postulate.

    to assert a first cause as necessary.


idioms

  1. assert oneself, to insist on one's rights, declare one's views forcefully, etc..

    The candidate finally asserted himself about property taxes.

assert British  
/ əˈsɜːt /

verb

  1. to insist upon (rights, claims, etc)

  2. (may take a clause as object) to state to be true; declare categorically

  3. to put (oneself) forward in an insistent manner

"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

Related Words

See declare. See maintain.

Other Word Forms

Etymology

Origin of assert

First recorded in 1595–1605; from Latin assertus “joined to, defended, claimed,” past participle of asserere “to join to, defend,” from as- as- + serere “to connect” ( cf. series)

Explanation

Asserting is all about standing up for what you believe. You might assert an opinion, your innocence, or even your authority over someone else. The verb assert can be used for both opinions and for oneself. When asked, you can politely assert your desire to go to the amusement park for your birthday. If no one listens to you, you can assert yourself and forcefully state that you really want to go to the amusement park for your birthday. If that fails, you should just take yourself to the amusement park for your birthday. And get better friends.

Keep Reading on Vocabulary.com

Vocabulary lists containing assert

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.

Appeared in the January 6, 2026, print edition as 'New Regime Is Rushing to Assert Control'.

From The Wall Street Journal • Jan. 5, 2026

The members of the Holy Alliance intended also to Assert Fernando VII’s control over his rebellious American colonies.

From Textbooks • Dec. 14, 2022

Assert sweeping claims of executive privilege, they advised him, after Mr. Corcoran had suggested that an unspecified “chief judge” would ultimately validate their belief that a president’s powers extend far beyond their time in office.

From New York Times • Sep. 16, 2022

Assert executive privilege, thereby creating “a new legal battleground to protect himself.”

From Slate • Apr. 11, 2018

"Assert thy power, lift up thy hand and strike, that all men may fear to infringe thy privilege as lord of the sea."

From Stories from the Odyssey by Havell, H. L. (Herbert Lord)