complainer vs squawker

complainer and squawker both are nouns.

Word	Noun	Adjective	Verb	Adverb
complainer	Yes	No	No	No
squawker	Yes	No	No	No

As nouns, complainer and squawker are synonyms defined as:

complainer and squawker: a person given to excessive complaints and crying and whining

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

complainer (noun)	squawker (noun)
a person given to excessive complaints and crying and whining	the loudspeaker on an intercom or public address system
	a person given to excessive complaints and crying and whining