Gnaeus Pompeius Magnus vs Pompey

Gnaeus Pompeius Magnus and Pompey both are nouns.

Word	Noun	Adjective	Verb	Adverb
Gnaeus Pompeius Magnus	Yes	No	No	No
Pompey	Yes	No	No	No

As nouns, Gnaeus Pompeius Magnus and Pompey are synonyms defined as:

Gnaeus Pompeius Magnus and Pompey: Roman general and statesman who quarrelled with Caesar and fled to Egypt where he was murdered (106-48 BC)

Other synonyms of Gnaeus Pompeius Magnus include Pompey the Great.

Gnaeus Pompeius Magnus (noun)	Pompey (noun)
Roman general and statesman who quarrelled with Caesar and fled to Egypt where he was murdered (106-48 BC)	a port city in southern England on the English Channel; Britain's major naval base
	Roman general and statesman who quarrelled with Caesar and fled to Egypt where he was murdered (106-48 BC)