occur between other event or between certain points of time; "the war intervened between the birth of her two children"
get involved, so as to alter or hinder an action, or through force or threat of force; "Why did the U.S. not intervene earlier in WW II?"
be placed or located between other things or extend between spaces and events; "This interludes intervenes between the two movements"; "Eight days intervened"
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!"
march aggressively into another's territory by military force for the purposes of conquest and occupation; "Hitler invaded Poland on September 1, 1939"
penetrate or assault, in a harmful or injurious way; "The cancer had invaded her lungs"
occupy in large numbers or live on a host; "the Kudzu plant infests much of the South and is spreading to the North"
absolutely required and not to be used up or sacrificed
absolutely necessary; vitally necessary; "essential tools and materials"; "funds essential to the completion of the project"; "an indispensable worker"
being or relating to or containing the essence of a plant etc; "essential oil"