noun

• (countable) The digit or figure 4; an occurrence thereof.
• (countable) Anything measuring four units, as length.
• Four o'clock.
• A person who is four years old.
• (cricket, countable) An event in which the batsmen run four times between the wickets or, more often, a batsman hits a ball which bounces on the ground before passing over a boundary, resulting in an award of 4 runs for the batting team. If the ball does not bounce before passing over the boundary, a six is awarded instead.
• (basketball, countable) A power forward.
• (rowing) Four-man sweep racing shell, with or without a coxswain.
• The shell itself.
• The crew rowing in a four boat.
• (colloquial) A regatta event for four boats.
• (obsolete) A four-pennyworth of spirits.