Definition of alter
- an event that altered the course of history
- customs that alter with the times
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.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'alter.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
: 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
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