biodefense vs biological defence

biodefense and biological defence both are nouns.

Word	Noun	Adjective	Verb	Adverb
biodefense	Yes	No	No	No
biological defence	Yes	No	No	No

As nouns, biodefense and biological defence are synonyms defined as:

biodefense and biological defence: procedures involved in taking defensive measures against attacks using biological agents

Other synonyms of biodefense include biodefence, biological defense.

biodefense (noun)	biological defence (noun)
procedures involved in taking defensive measures against attacks using biological agents	procedures involved in taking defensive measures against attacks using biological agents