weatherboard vs windward side

weatherboard and windward side both are nouns.

Word	Noun	Adjective	Verb	Adverb
weatherboard	Yes	No	No	No
windward side	Yes	No	No	No

As nouns, weatherboard and windward side are synonyms defined as:

Other synonyms of weatherboard include weather side.

weatherboard (noun)	windward side (noun)
the side toward the wind	the side toward the wind
a long thin board with one edge thicker than the other; used as siding by lapping one board over the board below