number one noun 9adjective 2forms 1 noun9 •Someone who is top of a ranking, who is ranked first.Djokovic came through 6-4 6-1 1-6 6-3 to end Nadal's reign as Wimbledon champion, before overtaking the Spaniard as world number one on Monday. — 2011 •The single that has sold the most in a given period. •The most important person, the one who is in charge. •Oneself, being considered foremost, as by an egoist.No man should have more than two attachments—the first, to number one, and the second to the ladies; that's what I say—ha! ha! — 1836 •(informal, euphemistic) Urine; urination.He might have got up, without the bell's sounding, to do his number one, or number two, in his great big white chamber-pot. — 1953 •The main goalkeeper of a team, so-called because they wear the number 1 on the back of their kit. •The batsman who opens the batting. •A first lieutenant. •A large town where theatrical performances may expect to achieve success. adjective2 •First; foremost; best, often used after its headword.Commuting to work is the number one reason to own a car.He is my enemy number one. •(US, slang) Black, African-American. formsnumber ones
