aqueous humour vs British spelling

aqueous humour and British spelling both are nouns.

Word	Noun	Adjective	Verb	Adverb
aqueous humour	Yes	No	No	No
British spelling	Yes	No	No	No

aqueous humour (noun)	British spelling (noun)
the limpid fluid within the eyeball between the cornea and the lens	English orthography used in the UK, Ireland and most of the Commonwealth (characterized by 'analyse', 'centre' and 'useable')