1

once

play
adverb \ˈwən(t)s\

Definition of once

  1. 1 :  one time and no more rode a horse only once went skydiving once

  2. 2 :  at any one time :  under any circumstances :  ever didn't once thank me

  3. 3 :  at some indefinite time in the past :  formerly was once a booming mining town

  4. 4 :  by one degree of relationship first cousin once removed

once and for all

  1. 1 :  with finality :  definitively The team proved once and for all that they are the best.

  2. 2 :  for the last time I'm telling you once and for all that I'm not going.

once in a while

  1. :  now and then spent most of their time at home, but went out once in a while

Examples of once in a sentence

  1. I will repeat the question once.

  2. The play was performed only once.

  3. She didn't once thank me.

  4. He didn't look at me once.

  5. It was once done that way.

  6. A river once flowed through this canyon.

  7. It was once a booming mining town.

  8. Their music was once very popular.

Origin and Etymology of once

Middle English ones, from genitive of on one


First Known Use: 12th century


2

once

noun

Definition of once

  1. :  one single time :  one time at least Please be on time this once.

at once

  1. 1 :  at the same time :  simultaneously

  2. 2 :  immediately

  3. 3 :  2both at once funny and sad

Examples of once in a sentence

  1. I have tried Indian food more than once.

  2. Please be on time just this once.

  3. For once you seem to know what I'm talking about.

Origin and Etymology of once

see 1once


First Known Use: 13th century


3

once

adjective

Definition of once

  1. :  that once was :  former a once successful actor

Examples of once in a sentence

  1. the once child star is now a lawyer in the entertainment industry

Origin and Etymology of once

see 1once


First Known Use: 1620


4

once

conjunction

Definition of once

  1. :  at the moment when :  as soon as Once she spoke, I recognized her.

Examples of once in a sentence

  1. Once she spoke, I recognized her.

  2. you should have stopped wrestling once you knew someone was getting hurt, not five minutes later

Origin and Etymology of once

see 1once


First Known Use: 1747



ONCE Defined for English Language Learners

1

once

play
adverb \ˈwən(t)s\

Definition of once for English Language Learners

  • : one time only

  • : at any one time

  • : at some time in the past


2

once

noun

Definition of once for English Language Learners

  • : one single time


4

once

conjunction

Definition of once for English Language Learners

  • : at the moment when : as soon as


ONCE Defined for Kids

1

once

play
adverb \ˈwəns\

Definition of once for Students

  1. 1 :  one time only It happened just once.

  2. 2 :  at some time in the past :  formerly It was once done that way.

  3. 3 :  at any one time :  ever She didn't once thank me.

once and for all

  1. :  now and for the last time That should solve the problem once and for all.

once in a while

  1. :  from time to time I play golf once in a while.


2

once

play
noun

Definition of once for Students

  1. :  one single time We can make an exception just this once.

at once

  1. 1 :  at the same time I can't understand with both of you talking at once.

  2. 2 :  immediately 2 Leave at once.


3

once

play
conjunction

Definition of once for Students

  1. :  as soon as :  when Once you've finished your homework, you may go outside.



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