hovercraft vs ground-effect machine

hovercraft and ground-effect machine both are nouns.

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

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

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

hovercraft (noun)	ground-effect machine (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