(basketball, soccer) A defense in which each player covers an area of the court.

(law, humorous) Any legal strategy or propaganda strategy that seeks to overwhelm its audience with nonsensical arguments, as a way of confusing the audience and drowning out legitimate opposing arguments.

All the methods and procedures involved in defending against attack by chemical agents.

(law) A plea to the effect that from some formal defect (e.g. misnomer, lack of jurisdiction) the proceedings should be abated.

Any defensive measure against an attack by missiles etc while in space

(video games) A style of real-time strategy video game in which the player attempts to stop enemies from crossing a map by building traps to slow them down and towers or turrets which shoot at them as they pass within range.

Efforts to protect the citizens of a state from military attack.

(academy) The final step in earning a doctorate: an oral examination in which the doctorand publicly defends his/her thesis to the examiners.

(US, law) A legal defense in which the defendant claims to have committed a crime in the belief that he/she was not in the real world, but in a simulated reality.

plural of thesis defense