primer vs priming coat

primer and priming coat both are nouns.

Word	Noun	Adjective	Verb	Adverb
primer	Yes	No	No	No
priming coat	Yes	No	No	No

As nouns, primer and priming coat are synonyms defined as:

primer and priming coat: the first or preliminary coat of paint or size applied to a surface

Other synonyms of primer include flat coat, ground, primer coat, priming, undercoat.

primer (noun)	priming coat (noun)
any igniter that is used to initiate the burning of a propellant	the first or preliminary coat of paint or size applied to a surface
the first or preliminary coat of paint or size applied to a surface
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