defence
The rebels' only form of defence against the soldiers' guns was sticks and stones.
The local commanders have been building up their defences against invasion.
White blood cells are the body's principal defence against invading microbes.

SMART Vocabulary: related words and phrases

Defending and protecting
air defence
anti-bug
anti-mosquito
baby
bandobast
cocoon
defensive
duck and coveridiom
embedded
featherbedding
fight back
foot patrol
hedge
insulate
poisonous
security light
self-protective
self-protectiveness
shelter
sheltered

You can also find related words, phrases, and synonyms in the topics:

Backing, supporting & defending