disc plough vs moldboard plow

disc plough and moldboard plow both are nouns.

Word	Noun	Adjective	Verb	Adverb
disc plough	Yes	No	No	No
moldboard plow	Yes	No	No	No

As nouns, moldboard plow is a hypernym of disc plough; that is, moldboard plow is a word with a broader meaning than disc plough:

disc plough: a plow that consists of a gang of concave steel cutting disks, used for work in hard dry soils.
moldboard plow: plow that has a moldboard

Other hypernyms of disc plough include mouldboard plough.

disc plough (noun)	moldboard plow (noun)
a plow that consists of a gang of concave steel cutting disks, used for work in hard dry soils.	plow that has a moldboard