smidge vs smidgin

smidge and smidgin both are nouns.

Word	Noun	Adjective	Verb	Adverb
smidge	Yes	No	No	No
smidgin	Yes	No	No	No

As nouns, smidge and smidgin are synonyms defined as:

Other synonyms of smidge include iota, scintilla, shred, smidgen, smidgeon, tittle, whit.

smidge (noun)	smidgin (noun)
a tiny or scarcely detectable amount	a tiny or scarcely detectable amount