Definitions

1. noun

a person bearing the surname O’Brien, of Irish origin.

“The O’Brien family has been living in this area for generations.”

2. noun

a Gaelic title of nobility, equivalent to a baron or viscount.

“The O’Brien is a powerful noble family in Ireland.”

3. verb

to act or behave like the O’Brien family.

“He’s been obriening all his life, always putting others first.”

4. verb

to play the role of an O’Brien in a theatrical performance.

“The actor had to obrien to get into character.”