The word liners is a noun. It is the plural noun of liner.
Chimney liners are almost always used in chimneys to keep them clear and to protect them from wear and tear. For the most part, chimney liners are made out of clay and other similar materials.
The part of speech for this particular word is a noun.
part of speech
The part of speech for "answer" is a noun.
what part of speech is beneath
adverb
For protective reasons, wooden caskets are sometimes equipped with inner metal liners. Traditionally, these liners have been made from lead (the bottom part and the lid of the liner can be soldered together to provide a hermetical seal). In the US, the lead liners have been replaced by copper or bronze liners.
The part of speech for "explicit" is an adjective.
The part of speech for "lecturer" is a noun.
The part of speech for "rapid" is an adjective.
The part of speech of "came" is a verb.
The part of speech for "breezy" is an adjective.