water of crystallisation vs British spelling

water of crystallisation and British spelling both are nouns.

Word	Noun	Adjective	Verb	Adverb
water of crystallisation	Yes	No	No	No
British spelling	Yes	No	No	No

water of crystallisation (noun)	British spelling (noun)
the water present in hydrated compounds	English orthography used in the UK, Ireland and most of the Commonwealth (characterized by 'analyse', 'centre' and 'useable')