Aqua-Lung vs scuba

Aqua-Lung and scuba both are nouns.

Word	Noun	Adjective	Verb	Adverb
Aqua-Lung	Yes	No	No	No
scuba	Yes	No	No	No

As nouns, Aqua-Lung and scuba are synonyms defined as:

Aqua-Lung and scuba: a device (trade name Aqua-Lung) that lets divers breathe under water; scuba is an acronym for self-contained underwater breathing apparatus

Other synonyms of Aqua-Lung include aqualung.

Aqua-Lung (noun)	scuba (noun)
a device (trade name Aqua-Lung) that lets divers breathe under water; scuba is an acronym for self-contained underwater breathing apparatus	a device (trade name Aqua-Lung) that lets divers breathe under water; scuba is an acronym for self-contained underwater breathing apparatus