linear metre vs linear meter

linear metre and linear meter both are nouns.

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

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

linear metre and linear meter: a meter in which the deflection of the pointer is proportional to the quantity measured.

linear metre (noun)	linear meter (noun)
a meter in which the deflection of the pointer is proportional to the quantity measured.	a meter in which the deflection of the pointer is proportional to the quantity measured.