drilling platform vs drill rig

drilling platform and drill rig both are nouns.

Word	Noun	Adjective	Verb	Adverb
drilling platform	Yes	No	No	No
drill rig	Yes	No	No	No

As nouns, drill rig is a hypernym of drilling platform; that is, drill rig is a word with a broader meaning than drilling platform:

drilling platform: drilling rig consisting of an offshore platform (floating or fixed to the sea bed) from which many oil wells can be bored radially
drill rig: rig used in drilling for oil or gas

Other hypernyms of drilling platform include drilling rig, oil rig, oilrig.

drilling platform (noun)	drill rig (noun)
drilling rig consisting of an offshore platform (floating or fixed to the sea bed) from which many oil wells can be bored radially	rig used in drilling for oil or gas