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Tonia Thai
2021-10-31 11:10
Know (one's) onions British old-fashioned informal verb phrase
If you know your onions, you are very knowledgeable about something.
When it comes to history, she really knows her onions.
He knows his onion in the formation of the stars.
Said when someone has the skill or competence in something and could use it anywhere
To have lots of information about a topic that is usually not widely known.
To have experience and understand of how bad or unplesant something is
A subject one knows a lot about, or likes a lot
If you say that something is (not) your department, you mean that it's (not) your area of expertise or responsibility.
The verb "know" should be conjugated according to its tense.
Somewhat surprisingly, the origin of "know one's onions" is American from the 1920s. At the time, there was a whole host of expressions that meant the same thing - know your oats, know your apples, know your eggs, etc where virtually anything could be replaced by onions. Some of these, like the onions expression, have survived but no one can tell us why. Perhaps just too many everyday things can be substituted for stuff. Another theory but not proven is that it derives from rhyming slang, onion rings/things but Americans as a general rule are not into rhyming slang so this origin is most unlikely.
Do you see anything wrong?
Extremely ugly; unlovely; unattractive
I hate frogs because they’re as ugly as sin.
