Wordnet 3.0
VERB (2)
1. 
 start playing; 
- Example: "The musicians struck up a tune"[syn: sound off, strike up]
2.  begin; 
- Example: "strike up a conversation"
- Example: "strike up a friendship"
WordNet (r) 3.0 (2006):
strike up
    v 1: start playing; "The musicians struck up a tune" [syn:
         sound off, strike up]
    2: begin; "strike up a conversation"; "strike up a friendship"