From Longman Dictionary of Contemporary Englishguyguy /ɡaɪ/ ●●● S1 W3 noun [countable] 1 informalMAN a man SYN bloke Dave’s a nice guy when you get to know him. Jake’s a real tough guy.► see thesaurus at man2 TMC British English a model of a man burnt every year on Guy Fawkes Night, in Britain3 (also guy rope)DLO a rope that stretches from the top or side of a tent or pole to the ground to keep it in the right position4 → guys5 → no more Mr Nice Guy! → wise guy at wise1(5)COLLOCATIONSadjectivesa nice/good guyPeople say he’s a nice guy.a great guyPhil is a great guy and a lot of fun.the bad guy (=a man in a book or movie who does bad things)The bad guys all have guns.the good guy (=a man in a book or movie who does good things and beats the bad characters)He’s one of the good guys in the 'Star Wars' films.a bad guy (=a person who is responsible for something bad that happens, or a person who you do not like)I'm fed up with people always thinking that I am the bad guy.Mike's not a bad guy.the poor guy (=used when something bad happens to someone and you want to show sympathy)The poor guy was robbed of all his money.a tough guy (=a man who is strong and not afraid, especially one who is good at fighting)He’s trying to prove he’s a tough guy.a regular guy American English (=an ordinary man)I knew him in high school. He’s just a regular guy.the little guy American English (=ordinary people rather than a powerful organization such as a government or a large company)He wanted to get elected and fight for the little guy.
Examples from the Corpusguy• I saw a guy with a head the size of a bucket-the kind you put mops in.• I've put the finger on seven members of the ring since lunch, but the big guy is slippery.• Two chauffeurs linger in the corner, one white with blond hair, the other a good-looking black guy.• But you only need a few guys like me and you could.• It was sheer bloody hell listening to all those fatuous nincompoops saying what a great guy you are.• Dave's a really nice guy.• Nine guys played, and nine guys accomplished something.• Married veterans or guys who married when they got back had difficulties, too.• There's some guy who wants to talk to you.• Is he the guy who used to live next door to you?• These guys believed in what they were doing.Origin guy 1. (1800-1900) Guy Fawkes (1570-1606), who tried to blow up the English parliament. 2. (1300-1400) Probably from Dutch gei “type of rope”