- 1 accustomed to something/to doing something familiar with something and accepting it as normal or usual synonym used to accustomed to something to become/get accustomed to something My eyes slowly grew accustomed to the dark. This was not the kind of behavior I was accustomed to. accustomed to doing something She was a person accustomed to having eight hours' sleep every night.
- 2[usually before noun] (formal) usual synonym habitual He took his accustomed seat by the fire. opposite unaccustomed