- hair
- noun
1 (U) the mass of things like fine threads that grows on your head: She brushed her hair. | I must get my hair cut - it's getting too long. | blond/red/dark hair: Emma's the one with the red hair. | short/long/shoulder-length hair: Jane has long blond hair. | straight/curly/wavy/thick hair: Her long wavy hair was tied back with a bow. | dark-haired/fair-haired/short-haired etc: He's a tall, fair-haired guy.2 (C) one of the long fine things like thread that grows on people's heads and on other parts of their bodies, or similar things that grow on animals: The cat has left white hairs all over the sofa.3 get in sb's hair informal to annoy someone, especially by always being near them4 keep your hair on spoken used to tell someone to keep calm and not get annoyed5 let your hair down informal to enjoy yourself and start to relax, especially after working very hard: The party gave us all a chance to really let our hair down.6 make sb's hair stand on end to make someone very frightened7 not have a hair out of place to have a very neat appearance8 not turn a hair to remain completely calm when something bad or surprising suddenly happens9 not harm/touch a hair of sb's head to not harm someone in any way10 the hair of the dog (that bit you) humorous an alcoholic drink that you drink to cure a headache caused by drinking too much alcohol the night before—see also: have a good/fine head of hair head 1 (4), —see also: not see hide nor hair of hide 2 (4), split hairs split 1 (7), tear your hair (out) tear 2 (11)
Longman dictionary of contemporary English. 2004.