timber vs sternpost

timber and sternpost both are nouns.

Word	Noun	Adjective	Verb	Adverb
timber	Yes	No	No	No
sternpost	Yes	No	No	No

As nouns, sternpost is a hyponym of timber; that is, sternpost is a word with a more specific, narrower meaning than timber:

Other hyponyms of timber include coulisse, stringer, two-by-four.

timber (noun)	sternpost (noun)
a beam made of wood	(nautical) the principal upright timber at the stern of a vessel
a post made of wood
(music) the distinctive property of a complex sound (a voice or noise or musical sound)
land that is covered with trees and shrubs
the wood of trees cut and prepared for use as building material