A joke in which the object is to take a common word that ends in the sound "er" and add "I hardly know her!" after it for comedic effect. The end result is a sentence that can be perceived as a sexual innuendo or some other joke but oftentimes makes absolutely no sense whatsoever. Very few words that end in "er" make the sentence actually plausible, but there are a few notable examples as described in the examples section.

It is frowned upon to use professions or adjectives such as "Baker" or "Taller" as they can be considered cheating and anyone who uses them clearly has no imagination. Words such as "Toaster" or "Thriller" are acceptable, and names like "Lauer" are also acceptable.

The goal of the joke is to find a word ending with the sound "er". That being said, the word itself doesn't necessarily have to end with the letters "er". There are some cases where it ends in "re". "Creature" and "Tire" are some notable exceptions. These are acceptable.
"Binder? I hardly know her!"

"Sewer? I hardly know her!"

Phil: Sam, will you pass me that bottle of liquor?
Sam: Liquor? I hardly know her!
by Bugsy McGee February 24, 2011
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a joke when someone says any thing with er at the end
what thers a bomber i hardly know her HEHEHWHHEHHHHHHEHEHHEHHEHEUBFHYHNUHH
by inosuke fanboy October 20, 2021
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a saying karl jacobs uses.

whenever something ends with “her” and you wanna make someone laugh say “*word*? i hardly know her”
bleacher? i hardly know her”
by cumsob10 May 11, 2022
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Another way to add sex to innocent things without saying "that's what she said."

in (word ending in "er) her, i hardly know her, "Her" is the same person as "She" in that's what she said. It's a hypothetical girl that you have sex with.

When someone says a word ending in "er" you turn it into a sex joke.

So if a friend says, "Dude, I broke your windsheild wiper."
You say, "Wipe her? I hardly know her!"
Friend: You're such a messy eater
You: Eat her? I hardly know her!

Friend: Shut up, you fucker.
You: Fuck her? I hardly know her!

that's how to use: (word ending in "er) her, i hardly know her
by The monkey's Uncle. June 21, 2008
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