The Oxford Thesaurus An A-Z Dictionary of Synonyms - breachn.

1) break, violation, infraction, disobedience, non-observance, infringement, contravention: Their failure to comply with paragraph 3 is a clear breach of our contract. 2) break, rift, gulf, split, break-up, separation, rupture, severance, schism, split, alienation, estrangement: There seems to be no way to heal the breach between them. 3) gap, fissure, crack, split, hole, opening; chasm: Their cannon opened a breach in the castle wall. --v. 4) rupture; break through, invade: The sea has breached the dyke. Someone breached the security measures set up for the missile design.