Crab vs Cancer the Crab

Crab and Cancer the Crab both are nouns.

Word	Noun	Adjective	Verb	Adverb
Crab	Yes	No	No	No
Cancer the Crab	Yes	No	No	No

As nouns, Crab and Cancer the Crab are synonyms defined as:

Crab and Cancer the Crab: the fourth sign of the zodiac; the sun is in this sign from about June 21 to July 22

Other synonyms of Crab include Cancer.

Crab (noun)	Cancer the Crab (noun)
the fourth sign of the zodiac; the sun is in this sign from about June 21 to July 22	the fourth sign of the zodiac; the sun is in this sign from about June 21 to July 22
(astrology) a person who is born while the sun is in Cancer