ground-effect machine vs hovercraft

ground-effect machine and hovercraft both are nouns.

Word	Noun	Adjective	Verb	Adverb
ground-effect machine	Yes	No	No	No
hovercraft	Yes	No	No	No

As nouns, ground-effect machine and hovercraft are synonyms defined as:

ground-effect machine and hovercraft: a craft capable of moving over water or land on a cushion of air created by jet engines

ground-effect machine (noun)	hovercraft (noun)
a craft capable of moving over water or land on a cushion of air created by jet engines	a craft capable of moving over water or land on a cushion of air created by jet engines