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English definition of “by”

by

preposition uk   /baɪ/ us  

by preposition (AGENT)

A2 used to show the person or thing that does something: The motorcycle was driven by a tiny bald man. We were amazed by what she told us. I'm reading some short stories (written) by Chekhov. The book was translated by a well-known author. I felt frightened by the anger in his voice.

by preposition (METHOD)

A2 used to show how something is done: They travelled across Europe by train/car. She did the decorating (all) by herself (= alone, without help from anyone). We went in by (= through) the front door. Do you wish to be paid in cash or by cheque? He learned English by listening to the radio. Suddenly, she grabbed him by the arm (= took hold of this part of his body). I refuse to live by (= following) their rules.

by preposition (NOT LATER THAN)

A2 not later than; at or before: She had promised to be back by five o'clock. The application must be in by the 31st to be accepted. By the time I got to the station the train had already gone.

by preposition (MEASUREMENT)

B2 used to show measurements or amounts: Our office floor space measured twelve metres by ten (= was twelve metres in one direction and ten in the other). Their wages were increased by 15 percent. Freelance workers are paid by the hour (= for every hour they work). These phones have sold by the thousand.

by preposition (DURING)

during: We travelled by night and rested by day.
by nature, profession, trade, etc. used when describing someone's character, job, etc.: She is, by nature, a sunny, positive sort of a person. He's a plumber by trade. She was, by profession, a lawyer.
be all right/fine by sb If something is all right/fine by someone, they agree that it can happen: "I'd prefer to go later." "That's fine by me." If it's all right by you, I'd like to leave now.
Idioms

by

(Definition of by from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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