L/100 km vs unit of measurement

L/100 km and unit of measurement both are nouns.

Word	Noun	Adjective	Verb	Adverb
L/100 km	Yes	No	No	No
unit of measurement	Yes	No	No	No

As nouns, unit of measurement is a hypernym of L/100 km; that is, unit of measurement is a word with a broader meaning than L/100 km:

L/100 km: a measure of fuel consumption for vehicles, equal to the amout of liters of gasoline or diesel used to travel a distance of one hundred kilometers.
unit of measurement: any division of quantity accepted as a standard of measurement or exchange

Other hypernyms of L/100 km include unit.

L/100 km (noun)	unit of measurement (noun)
a measure of fuel consumption for vehicles, equal to the amout of liters of gasoline or diesel used to travel a distance of one hundred kilometers.	any division of quantity accepted as a standard of measurement or exchange