two-furrow plow vs two-furrow plough

two-furrow plow and two-furrow plough both are nouns.

Word	Noun	Adjective	Verb	Adverb
two-furrow plow	Yes	No	No	No
two-furrow plough	Yes	No	No	No

As nouns, two-furrow plow and two-furrow plough are synonyms defined as:

Other synonyms of two-furrow plow include double-furrow plough, double-furrow plow.

two-furrow plow (noun)	two-furrow plough (noun)
a plough with two moldboards.	a plough with two moldboards.