work together on a common enterprise of project; "The soprano and the pianist did not get together very well"; "We joined forces with another research group"
cooperate as a traitor; "he collaborated with the Nazis when they occupied Paris"
leave behind empty; move out of; "You must vacate your office by tonight"
leave (a job, post, or position) voluntarily; "She vacated the position when she got pregnant"; "The chairman resigned when he was found to have misappropriated funds"
a device that signals the occurrence of some undesirable event
an automatic signal (usually a sound) warning of danger
fear resulting from the awareness of danger
warn or arouse to a sense of danger or call to a state of preparedness; "The empty house alarmed him"; "We alerted the new neighbors to the high rate of burglaries"