Collocations for defence - noun

adequate, effective
immune, natural
the body's natural defence against viruses

homeland (AmE), national, territorial
air
civil
nuclear

come to, leap to, rush to, spring to
He always sprang to Rose's defence when Ed tried to criticize her.

in defence of
to fight in defence of your country

defence against
defence against attacks from the north

weapons of defence

effective, strong
coastal, sea
perimeter (AmE)
Perimeter defences around airports and government buildings should be strengthened.

anti-missile, missile

put up
They put up an effective defence against the guerrilla forces.

bolster, improve, strengthen
weaken
destroy, overcome, overwhelm
With her tears she completely overwhelmed his defences.

build, build up, rebuild
They are building up defences along the river.

breach, penetrate
The sea breached the coastal defences in a number of spots.

mechanism

defence against

capability, establishment, force, forces, system
Defense Department, Defense Secretary (in the US)
minister, ministry (in the UK)
policy, strategy
analyst, expert, planner
contractor, industry
budget, cuts, expenditure, spending

good
robust, solid, spirited, staunch, stout (BrE), strong, vigorous
adequate
legal
insanity (esp. AmE)
The judge rejected her insanity defence.

conduct, make, mount, offer, put up, raise

attorney (AmE), counsel, lawyer, team
witness

in sb's defence
She spoke in his defence.

defence of, defence to
a defence to murder

counsel for the defence

good, solid, staunch (esp. BrE), stout (BrE), strong

play (AmE)
put up
destroy, penetrate
improve, strengthen, upgrade (AmE)

in defence (BrE), on defence (AmE)
to play in defence
He plays on defence.