scoinson arch vs sconcheon arch

scoinson arch and sconcheon arch both are nouns.

Word	Noun	Adjective	Verb	Adverb
scoinson arch	Yes	No	No	No
sconcheon arch	Yes	No	No	No

As nouns, scoinson arch and sconcheon arch are synonyms defined as:

scoinson arch and sconcheon arch: an arch that supports part of the wall

scoinson arch (noun)	sconcheon arch (noun)
an arch that supports part of the wall	an arch that supports part of the wall