diminished arch vs scheme arch

diminished arch and scheme arch both are nouns.

Word	Noun	Adjective	Verb	Adverb
diminished arch	Yes	No	No	No
scheme arch	Yes	No	No	No

As nouns, diminished arch and scheme arch are synonyms defined as:

diminished arch and scheme arch: an arch whose height is less than half its width

Other synonyms of diminished arch include skeen arch, skene arch.

diminished arch (noun)	scheme arch (noun)
an arch whose height is less than half its width	an arch whose height is less than half its width