gee-gee vs Equus caballus

gee-gee and Equus caballus both are nouns.

Word	Noun	Adjective	Verb	Adverb
gee-gee	Yes	No	No	No
Equus caballus	Yes	No	No	No

As nouns, Equus caballus is a hypernym of gee-gee; that is, Equus caballus is a word with a broader meaning than gee-gee:

gee-gee: a word for horse used by children or in adult slang
Equus caballus: solid-hoofed herbivorous quadruped domesticated since prehistoric times

Other hypernyms of gee-gee include horse.

gee-gee (noun)	Equus caballus (noun)
a word for horse used by children or in adult slang	solid-hoofed herbivorous quadruped domesticated since prehistoric times