CFC vs greenhouse emission

CFC and greenhouse emission both are nouns.

Word	Noun	Adjective	Verb	Adverb
CFC	Yes	No	No	No
greenhouse emission	Yes	No	No	No

As nouns, greenhouse emission is a hypernym of CFC; that is, greenhouse emission is a word with a broader meaning than CFC:

CFC: a fluorocarbon with chlorine; formerly used as a refrigerant and as a propellant in aerosol cans
greenhouse emission: a gas that contributes to the greenhouse effect by absorbing infrared radiation

Other hypernyms of CFC include pollutant, fluorocarbon, greenhouse gas.

CFC (noun)	greenhouse emission (noun)
a fluorocarbon with chlorine; formerly used as a refrigerant and as a propellant in aerosol cans	a gas that contributes to the greenhouse effect by absorbing infrared radiation