windstorm vs sandstorm

windstorm and sandstorm both are nouns.

Word	Noun	Adjective	Verb	Adverb
windstorm	Yes	No	No	No
sandstorm	Yes	No	No	No

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

Other hyponyms of windstorm include cyclone, dust storm, duster, sirocco, tempest, whirlwind.

windstorm (noun)	sandstorm (noun)
a storm consisting of violent winds	a windstorm that lifts up clouds of dust or sand