1 : close to or next to (something or someone) : near
▪ She was standing by [=beside] the window. ▪ His wife was sitting by him. ▪ They have a house by the lake. 2 a : up to and beyond (something or someone) : past
▪ The bus went right by him without stopping.
b : at or to (someone's home)
▪ Some friends stopped/came by our house for a chat. ▪ Why don't you come by my place later? 3 a — used following a passive verb to indicate the person or thing that does something ▪ The decision was made by the company president. [=the company president made the decision] ▪ Coal has been replaced by oil. [=oil has replaced coal] ▪ He was killed by a falling rock. [=a falling rock killed him] ▪ I was greatly surprised by the result. [=the result surprised me greatly]
b — used to indicate the thing that is used to do something ▪ He opened the door by (using) force. [=he used force to open the door] ▪ She succeeded by pure determination.
c — used to indicate an action that is done for a particular purpose ▪ You can reset the machine by pressing this button. [=you can press this button to reset the machine] ▪ He began his speech by thanking the President and ended it by telling a joke. 4 — used to indicate the person who wrote or created something ▪ a play (written) by William Shakespeare ▪ This is a portrait of Gaugin (that was painted) by Van Gogh. 5 a — used to indicate the method used to go somewhere, send something, etc. ▪ Some people came by [=via] train while others came by car. ▪ He returned by [=on, via] the last train. ▪ They sent him a message by [=via] e-mail. ▪ We drove here by the back roads.
b — used to indicate the method used to enter or leave a place ▪ We entered by [=through, via] the front door. 6 a — used to indicate the name that is used for someone or something ▪ The American writer Samuel L. Clemens was known by the name “Mark Twain.” ▪ Her full name is Elizabeth but she goes by (the nickname) “Lizzie.” ▪ The Federal Bureau of Investigation is usually referred to by its initials “FBI.”
b — used to indicate how someone is spoken to, identified, etc. ▪ He called her by name. [=he used her name when he spoke to her] ▪ I know her by sight but not by name. [=I know what she looks like but I don't know her name]
c — used to introduce the name of someone or something important as proof that you are speaking the truth ▪ I swear by [=in the name of] all that's sacred that everything I've said is true. — often used in phrases like by God to add emphasis ▪ He always said he'd retire to Hawaii, and by God, he did it!
d : when using (a specified word or phrase)
▪ What do you mean by “acceptable levels?” [=what levels do you consider acceptable?] ▪ She called my theory “interesting,” but I don't know what she meant by that. [=I don't know whether she was being sincere, polite, etc.] ▪ It's hard to know what the author intended by this phrase. 7 — used to indicate the part of something or of a person's body that is held, grasped, etc. ▪ He grasped the shovel by the/its handle. [=he grasped the handle of the shovel] ▪ She grabbed him by the arm. [=she grabbed his arm] ▪ He held/took his daughter by the/her hand. [=he held/took his daughter's hand] 8 a : during the time of (day or night)
▪ New York by night [=at night, during the night] is very different from New York by day. [=during the day]
b — used to indicate the kind of light that occurs or is used when something is being looked at, read, etc. ▪ The landscape looked very different when we saw it by daylight than it had by moonlight. ▪ She was trying to read by the light of a single candle. 9 a : not later than (a specified time) : at, in, on, or before (a specified time)
▪ We need to leave by noon at the latest. ▪ They should be here by tomorrow. ▪ I don't know where she is. She should have been back by now. ▪ By this time next year she hopes to have a new job. ▪ She's planning to get married next year, by which time she hopes to have a new job.
b : during the time until (a specified time)
▪ By 2000 the U.S. had been an independent country for more than 200 years. 10 a : in a way that agrees with or follows (something, such as a rule)
▪ They didn't play by the rules.
b : in a way that is based on (something)
▪ You shouldn't judge other people by (their) appearances.
c : according to (something)
▪ By my watch it's nearly noon. [=my watch says that it's nearly noon] 11 a — used to indicate units of measurement or quantity ▪ The eggs are sold by the dozen. ▪ She gets paid by the hour. ▪ They have been making progress by small degrees.
b — used to indicate the number that multiplies or divides another number ▪ multiply 8 by 12 ▪ divide 10 by 4
c — used to indicate the numbers of a measurement ▪ The room measures 15 feet by 20 feet. 12 — used to indicate an amount, length, etc. ▪ The horse won the race by a nose. ▪ She's taller than I am by several inches. [=she's several inches taller than I am] ▪ The price has been increased by five dollars. ▪ This one is better by far than that one. [=this one is much better than that one] 13 — used to indicate someone's job, origin, character, etc. ▪ She's a lawyer by profession. ▪ He's French by birth, although he has lived in America for many years. ▪ I'm an optimist by nature. [=it is my nature to be optimistic] 14 a — used in phrases to describe the speed at which something happens or changes ▪ The work is getting done bit by bit. [=the work is getting done gradually in small amounts] ▪ He's getting better little by little. ▪ His health is growing worse day by day. = His health is growing worse by the day. [=his health is growing worse every day] ▪ The situation is getting more dangerous by the second/minute/hour.
b — used in phrases to describe how a series of people or things proceed or are dealt with ▪ They entered the room two by two. [=two at a time] [=two of them entered the room, then two more entered the room, etc.] ▪ I solved the problems one by one. [=I solved the first problem, then the second one, etc.] 15 informal : in the opinion of (someone)
▪ Whatever you want to do is fine/okay by me. [=I am willing to agree to whatever you want to do] 16 somewhat formal a : on behalf of (someone)
▪ He always did right by his children. [=he always did the right things to help his children]
b — used to indicate the husband or wife who is the parent of someone's child ▪ He had two daughters by his first wife and a son by his second wife. [=his first wife was the mother of his two daughters and his second wife was the mother of his son] ▪ She has two children by her first husband.