ward off, defend, protect, resist
防 centers on active defense: warding off threats, protecting against harm, and resisting attack.
防 combines ⻖ (hill, mound) with 方, which likely contributes the sound. The hill radical suggests an earthen barrier or rampart used for defense.
The left side ⻖ is a hill or mound, and the right side 方 looks like a direction or method. Picture building a defensive mound in every direction to ward off enemies.
For ボウ, imagine a bow (as in bow and arrow) used to defend a hill fort: bow -> ボウ, and the archer wards off attackers from the mound.
defense; defence; protection
to defend against; to protect against
prevention; check
prevention; protection (against); precaution
defense; defence; safeguard; protection
disaster preparedness; prevention of damage resulting from a natural disaster; protection against disaster
fire fighting
prevention of crime
national defence; national defense
waterproofing; making watertight
protection
bulletproof; bombproof
bank; weir; embankment; levee
offense and defense; offence and defence
fire station
fire engine; fire truck
soundproofing
air defense; air defence
fire prevention; fire control; fireproofing
breakwater; mole
Fire and Disaster Management Agency
communicable disease control (e.g. by quarantine, disinfection, etc.); prevention of epidemics
defensive fight (battle)
Japan Defense Agency (became Ministry of Defense in January 2007)