Cf vs metallic element

Cf and metallic element both are nouns.

Word	Noun	Adjective	Verb	Adverb
Cf	Yes	No	No	No
metallic element	Yes	No	No	No

As nouns, metallic element is a hypernym of Cf; that is, metallic element is a word with a broader meaning than Cf:

Cf: a radioactive transuranic element; discovered by bombarding curium with alpha particles
metallic element: any of several chemical elements that are usually shiny solids that conduct heat or electricity and can be formed into sheets etc.

Other hypernyms of Cf include metal.

Cf (noun)	metallic element (noun)
a radioactive transuranic element; discovered by bombarding curium with alpha particles	any of several chemical elements that are usually shiny solids that conduct heat or electricity and can be formed into sheets etc.