1 knowing sb/sth well
ADJ. detailed, greater, intimate | basic
VERB + FAMILIARITY have I had only a basic familiarity with computers. | acquire, gain Over the years, he gained greater familiarity with the culture and way of life in the country.
PREP. ~ with her detailed familiarity with her subject
PHRASES a lack of familiarity
2 friendly informal manner
ADJ. easy He treated her with the easy familiarity of an equal.