defend verb
1 protect against attack
PREP. against
PHRASES heavily defended The city was heavily defended against attack.
2 support
ADV. fiercely, hotly, robustly, staunchly, stoutly, strenuously, strongly, vigorously The company has strenuously defended its decision to reduce the workforce. | publicly
PREP. against She defended her department against accusations of incompetence.
3 in sport/competitions
ADV. successfully
PREP. against The champion successfully defended his title against the American challenger.
You can also check other dicts: defend (English, 中文解释 ), wordnet sense, Collins Definition