Definition of sister
- sister cities
The sisters live in the convent.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'sister.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
First Known Use: before 12th centurySee Words from the same year
: a girl or woman who has one or both of the same parents as you
—used when talking to a woman
: a member of a religious community of women
What made you want to look up sister? Please tell us where you read or heard it (including the quote, if possible).