Yb vs computer memory unit

Yb and computer memory unit both are nouns.

Word	Noun	Adjective	Verb	Adverb
Yb	Yes	No	No	No
computer memory unit	Yes	No	No	No

As nouns, computer memory unit is a hypernym of Yb; that is, computer memory unit is a word with a broader meaning than Yb:

Yb (noun)	computer memory unit (noun)
a unit of information equal to 1000 zettabits or 10^24 bits	a unit for measuring computer memory
a soft silvery metallic element; a rare earth of the lanthanide series; it occurs in gadolinite and monazite and xenotime