"had better, should, or ought to." Also can be used in front of any popular phrase, or as an adverb or subjunctive to describe an action or noun.
That's fidda crazy!
Fidda get rollin'!
Fidda please.
Fidda check yourself, before you wreck yourself.
Note that when using this word it may also feel correct and necessary to spell out the last word of the sentence in which fidda is used, and if it is a two-word sentence then you may only spell out that second and last word without saying it.
(Fidda funk that junk, j-u-n-k. OR Fidda r-o-l-l.
by Chapsworth November 4, 2007
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Someone who is acting in a strange or curious manner.
"Look at the way that guy is walking! He's must be on meth or something."

"Yeah mang that guy is definitely a foo fidda."
by hts mom February 16, 2009
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Vulgar slang for pussy, twat, cunt, vagina, etcetera in Scanian (Southern Swedish dialect).

Can be used as an insult or as its literal meaning: vagina.
IN SWEDISH
Guy: DIN JÄLA FIDDA!

IN ENGLISH (TRANSLATION)
Guy: YOU FUCKING PUSSY!
by Noveak-Prime April 1, 2021
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