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verb al·ter \ˈȯl-tər\

Simple Definition of alter

  • : to change (something)

  • : to make a change to (a piece of clothing) so that it will fit better

  • : to remove the sex organs of (an animal) so that the animal is unable to reproduce

Full Definition of alter

al·teredal·ter·ingplay \-t(ə-)riŋ\

  1. transitive verb
  2. 1 :  to make different without changing into something else

  3. 2 :  castrate, spay

  4. intransitive verb
  5. :  to become different

al·ter·abil·i·ty play \ˌȯl-t(ə-)rə-ˈbi-lə-tē\ noun
al·ter·able play \ˈȯl-t(ə-)rə-bəl\ adjective
al·ter·ably play \-blē\ adverb
al·ter·er play \-tər-ər\ noun

Examples of alter

  1. Alcohol can alter a person's mood.

  2. He altered his will to leave everything to his sister.

  3. This one small event altered the course of history.

  4. The place has altered in the 10 years since I left.

  5. I'll need to have the dress altered before the wedding.

Origin of alter

Middle English, from Medieval Latin alterare, from Latin alter other (of two); akin to Latin alius other — more at else

First Known Use: 14th century

Synonym Discussion of alter

change, alter, vary, modify mean to make or become different. change implies making either an essential difference often amounting to a loss of original identity or a substitution of one thing for another <changed the shirt for a larger size>. alter implies a difference in some particular respect without suggesting loss of identity <slightly altered the original design>. vary stresses a breaking away from sameness, duplication, or exact repetition <vary your daily routine>. modify suggests a difference that limits, restricts, or adapts to a new purpose <modified the building for use by the disabled>.

Rhymes with alter

Medical Dictionary


transitive verb al·ter \ˈȯl-tər\

Medical Definition of alter

al·teredal·ter·ing \-t(ə-)riŋ\play

  1. :  castrate 1, spay

Seen and Heard

What made you want to look up alter? Please tell us where you read or heard it (including the quote, if possible).


February 8, 2016

to clear from accusation or blame

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