undercoating
un-der-coat-ing
noun
A protective layer applied to a surface before the final coat of paint.
"The car needed undercoating to prevent rust."
verb
The action of applying a protective base layer to a surface.
"Undercoating the metal will prevent future corrosion."
Thesaurus
Synonyms: priming, primer coat, priming coat, primer, flat coat, undercoat, ground, prime, underseal, underfur