woodscrew vs lag screw

woodscrew and lag screw both are nouns.

Word	Noun	Adjective	Verb	Adverb
woodscrew	Yes	No	No	No
lag screw	Yes	No	No	No

As nouns, lag screw is a hyponym of woodscrew; that is, lag screw is a word with a more specific, narrower meaning than woodscrew:

woodscrew: a metal screw that tapers to a point so that it can be driven into wood with a screwdriver
lag screw: a heavy woodscrew with a square or hexagonal head that is driven in with a wrench

Other hyponyms of woodscrew include lag bolt, screw eye.

woodscrew (noun)	lag screw (noun)
a metal screw that tapers to a point so that it can be driven into wood with a screwdriver	a heavy woodscrew with a square or hexagonal head that is driven in with a wrench