weight unit vs metric unit

weight unit and metric unit both are nouns.

Word	Noun	Adjective	Verb	Adverb
weight unit	Yes	No	No	No
metric unit	Yes	No	No	No

As nouns, metric unit is a hypernym of weight unit; that is, metric unit is a word with a broader meaning than weight unit:

weight unit: a decimal unit of weight based on the gram
metric unit: a decimal unit of measurement of the metric system (based on meters and kilograms and seconds)

Other hypernyms of weight unit include metric, mass unit.

weight unit (noun)	metric unit (noun)
a unit used to measure weight	a decimal unit of measurement of the metric system (based on meters and kilograms and seconds)
a decimal unit of weight based on the gram