gal vs girl

gal and girl both are nouns.

Word	Noun	Adjective	Verb	Adverb
gal	Yes	No	No	No
girl	Yes	No	No	No

As nouns, girl is a hypernym of gal; that is, girl is a word with a broader meaning than gal:

Other hypernyms of gal include fille, miss, missy, young lady, young woman.

gal (noun)	girl (noun)
alliterative term for girl (or woman)	a young female
United States liquid unit equal to 4 quarts or 3.785 liters	a girl or young woman with whom a man is romantically involved
a unit of gravitational acceleration equal to one centimeter per second per second (named after Galileo)	a youthful female person
	a friendly informal reference to a grown woman
	a female human offspring