biological defense vs biodefence

biological defense and biodefence both are nouns.

Word	Noun	Adjective	Verb	Adverb
biological defense	Yes	No	No	No
biodefence	Yes	No	No	No

As nouns, biological defense and biodefence are synonyms defined as:

biological defense and biodefence: procedures involved in taking defensive measures against attacks using biological agents

Other synonyms of biological defense include biodefense, biological defence.

biological defense (noun)	biodefence (noun)
procedures involved in taking defensive measures against attacks using biological agents	procedures involved in taking defensive measures against attacks using biological agents