strike up a friendship

strike up

1. To initiate, instigate, or begin something. I saw you striking up a conversation with Jack—what did you two discuss? You might be able to strike up a deal with her if you mention your father's connection to the business. The detective and the con man struck up a unique friendship.
2. Of a band, to begin playing music. Can be used transitively or intransitively. The band struck up and got everyone dancing. Come on, boys, let's strike up a tune that'll really get this place hopping!
See also: strike, up
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

strike up a friendship

to become friends (with someone). I struck up a friendship with John while we were on a business trip together. If you're lonely, you should go out and try to strike up a friendship with someone you like.
See also: friendship, strike, up
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.
See also: