(informal) To not know; to have no idea.

(informal, idiomatic) To begin; to start some action; to set in motion.

(idiomatic) Something that intensifies the appreciation of something already good.

Used to introduce a new topic; incidentally, by the way.

Incidental; unplanned.

Used other than figuratively or idiomatically: see lose, plot. / (UK, idiomatic) To cease to behave in a consistent and/or rational manner.

To pick up the receiver of a telephone, generally with the intention of making a phone call. / To answer an incoming telephone call.

(idiomatic) Actively traveling; busy; moving often. / In progress; having started.

To go out onto the playing field. / To begin military operations. / (horse racing) To stake one's money against the favourite, taking the chances of the field against the chance of one horse.

(idiomatic) To discourage someone greatly; to cause someone to lose hope or the will to continue; to thwart or minimize someone's ambitions.