twiddler vs fiddler

twiddler and fiddler both are nouns.

Word	Noun	Adjective	Verb	Adverb
twiddler	Yes	No	No	No
fiddler	Yes	No	No	No

As nouns, twiddler and fiddler are synonyms defined as:

twiddler and fiddler: someone who manipulates in a nervous or unconscious manner

twiddler (noun)	fiddler (noun)
someone who manipulates in a nervous or unconscious manner	a musician who plays the violin
	an unskilled person who tries to fix or mend
	someone who manipulates in a nervous or unconscious manner