Wordnet 3.0
VERB (1)
1. 
 go against, as of rules and laws; 
- Example: "He ran afoul of the law"- Example: "This behavior conflicts with our rules"[syn: conflict, run afoul, infringe, contravene]
WordNet (r) 3.0 (2006):
run afoul
    v 1: go against, as of rules and laws; "He ran afoul of the
         law"; "This behavior conflicts with our rules" [syn:
         conflict, run afoul, infringe, contravene]