grumbler vs sniveller

grumbler and sniveller both are nouns.

Word	Noun	Adjective	Verb	Adverb
grumbler	Yes	No	No	No
sniveller	Yes	No	No	No

As nouns, grumbler and sniveller are synonyms defined as:

grumbler and sniveller: a person given to excessive complaints and crying and whining

Other synonyms of grumbler include bellyacher, complainer, crybaby, moaner, squawker, whiner.

grumbler (noun)	sniveller (noun)
a person given to excessive complaints and crying and whining	a person given to excessive complaints and crying and whining