square meter vs square metre

square meter and square metre both are nouns.

Word	Noun	Adjective	Verb	Adverb
square meter	Yes	No	No	No
square metre	Yes	No	No	No

As nouns, square meter and square metre are synonyms defined as:

square meter and square metre: a unit of measurement for area, defined as the area of a square with sides of exactly 1 metre; a centiare is 1/100th of an are

Other synonyms of square meter include centare.

square meter (noun)	square metre (noun)
a unit of measurement for area, defined as the area of a square with sides of exactly 1 metre; a centiare is 1/100th of an are	a unit of measurement for area, defined as the area of a square with sides of exactly 1 metre; a centiare is 1/100th of an are