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
Examples of alter in a sentence
Alcohol can alter a person's mood.
He altered his will to leave everything to his sister.
This one small event altered the course of history.
The place has altered in the 10 years since I left.
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
ALTER Defined for Kids
Definition of alter for Students
: to change partly but not completely <… each time he had altered his course. — Walter Farley, The Black Stallion>
Seen and Heard
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