Definition of Undercoating

Babylon English Dictionary
protective coating on the underside of an automobile
apply an undercoat (of paint, varnish, etc.)
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Undercoating Definition from Science & Technology Dictionaries & Glossaries
Dictionary of Automotive Terms
The material sprayed on the underside of the automobile, under the hood , trunk lid, etc. which is designed to deaden sound and prevent the formation of rust.
Undercoating Definition from Language, Idioms & Slang Dictionaries & Glossaries
WordNet 2.0

Noun
1. seal consisting of a coating of a tar or rubberlike material on the underside of a motor vehicle to retard corrosion
(synonym) underseal
(hypernym) seal
(derivation) prime, ground
2. the first or preliminary coat of paint or size applied to a surface
(synonym) flat coat, ground, primer, priming, primer coat, priming coat
(hypernym) coat of paint
(hyponym) couch
(derivation) prime, ground
3. thick soft fur lying beneath the longer and coarser guard hair
(synonym) underfur
(hypernym) fur

Verb
1. cover with a primer; apply a primer to
(synonym) prime, ground
(hypernym) paint
(derivation) underseal