Undercoat

v. apply an undercoat (of paint, varnish, etc.)

n. inner jacket; layer of short fur under a longer layer (Zoology); layer of paint underneath the outermost layer; undercoating

"Undercoat" redirects here, but this term is also used to mean a layer of paint below the top layer.Down hairs, also called the ground hairs, are the very fine, fluffy hairs closest to the skin on some mammals. The hairs are short and crimped, which makes them highly efficient for trapping air and insulating the animal. In the hobby of animal fancy, the down hair is collectively called the undercoat and is an important conformation point in shows, particularly dog and cat shows.
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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

(n.)
A growth of short hair or fur partially concealed by a longer growth; as, a dog's undercoat.
  

(n.)
A coat worn under another; a light coat, as distinguished from an overcoat, or a greatcoat.
  

1)The underlying layer of soft, smooth secondary hair that insulates a dog's coat.
2)The portion of a cat's coat beneath the topcoat that consists of down hairs.