harshly uninviting or formidable in manner or appearance; "a dour, self-sacrificing life"; "a forbidding scowl"; "a grim man loving duty more than humanity"; "undoubtedly the grimmest part of him was his iron claw"- J.M.Barrie
make submissive, obedient, or useful; "The horse was tough to break"; "I broke in the new intern"
break so as to call inward; "He broke in the door"
start in a certain activity, enterprise, or role
intrude on uninvited; "The nosy couple broke in on our conversation"
enter someone's property in an unauthorized manner, usually with the intent to steal or commit a violent act; "Someone broke in while I was on vacation"; "They broke into my car and stole my radio!"