gal vs young woman

gal and young woman both are nouns.

Word	Noun	Adjective	Verb	Adverb
gal	Yes	No	No	No
young woman	Yes	No	No	No

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

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

gal (noun)	young woman (noun)
alliterative term for girl (or woman)	a young female
United States liquid unit equal to 4 quarts or 3.785 liters
a unit of gravitational acceleration equal to one centimeter per second per second (named after Galileo)