biological defence vs biodefence

biological defence and biodefence both are nouns.

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

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

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

Other synonyms of biological defence include biodefense, biological defense.

biological defence (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