picometre vs British spelling

picometre and British spelling both are nouns.

Word	Noun	Adjective	Verb	Adverb
picometre	Yes	No	No	No
British spelling	Yes	No	No	No

picometre (noun)	British spelling (noun)
a metric unit of length equal to one trillionth of a meter	English orthography used in the UK, Ireland and most of the Commonwealth (characterized by 'analyse', 'centre' and 'useable')