1) A nonsensical term that is used to replace of a noun, thus making a sentence or phrase sound more dirty or inapropriate.

2) Dilby can also be used to replace a explitive (like dick) to "clean up" the the language in a phrase, while keeping the raunchy sound intact.

plural form:

Dilbies
ex.:
1) NORMAL SENTENCE:
Person A: "Wow, my butt is sore!"
Person B: "Why?"
Person A: "I sat on a chair that was rock-solid all day."

SENTENCE WITH A NOUN REPLACED BY "DILBY"

Person A: "Wow, my butt is sore!"
Person B: "Why?"
Person A: "I sat on a DILBY that was rock-solid all day."

2) Would ya look at the dilbies on that chick!
by MR.PR3Z August 25, 2009
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to DILBY means to insult someone extreamly badly.
by northey January 2, 2007
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A dilby is the person who we all know, they are notorious for being "that guy will do it" they seek attention and yearn to be wanted so bad that they will stop at nothing to gain it. They commonly will spend money on you while out, or if their broke, like most are, they will offer their services to you, "hey man want me to fix your car, take out your trash and clean your toilet?" And even sex if they are of the opposite side of the fence. They can be easily spotted in the crowd as the one who laughs at everything, and their laugh resembles the sound of brushing teeth.
Stop following me, i dont need help, your being a total dilby!
by Da Joka 6977 March 31, 2009
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A group of intellectuals with a dedicated friendship.
“Oh look, a dilby! Their friendship is so wild and crazy, but it’s so dedicated. Such a dilby, I swear my dude!”
by kingmonarch August 18, 2018
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Someone who is really dumbwitted, imbissolic and a wanna be cool cat.
May be used as a derogatory term.
After person 2 does something very idiotic --

Person 1 : Fuck your'e a dilby!

Person 2 : Stfu!
by Brossef!101 September 3, 2010
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