To make obedient, docile and tractable; to train to follow orders of the owner.  
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"
make submissive, obedient, or useful, as of wild animals or new items: "The horse was tough to break"; used metaphorically for people
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!"
break into a conversation; "her husband always chimes in, even wehn he is not involved in the conversation"
make submissive, obedient, or useful; "The horse was tough to break"; "I broke in the new intern"
break into a conversation; "her husband always chimes in, even when he is not involved in the conversation"
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!"
make submissive, obedient, or useful
break so as to fall inward
break into a conversation
intrude on uninvited
enter someone's (virtual or real) property in an unauthorized manner, usually with the intent to steal or commit a violent act
