A screwdriver with a '+' shaped head for turning screws so socketed. / A screw turned by such a screwdriver.

(idiomatic) An advantage consisting in starting a competition or task earlier than might be expected; given (or taken), for example, prior to the beginning of a race.

(idiomatic) To a considerable degree. / By force; violently.

In the United States, a government-funded preschool program for impoverished children.

(chiefly US, idiomatic) A warning or call to pay attention; an advisory notice; a notice of what is to happen; a holler.

With head directly above the neck, eyes front. / Alert; vigilant

The end of a mop, to which the thrums or rags are fastened. / (US) A clamp for holding the thrums or rags of a mop.

(informal) The person in charge; the highest-ranking person in an organization.

Alternative spelling of headcase

Alternative spelling of headcase / Used other than figuratively or idiomatically: see head, case.