防 -proof

Kanji Study : 防

Today we will look at a fairly common upper level kanji, 防.

As a verb it means:

ふせぐ 【防ぐ】 protect from, keep away, prevent

And we can see these meanings in 熟語 jukugo (kanji combinations), but another meaning for this kanji when used as a prefix is "-proof". Knowing this can increase your vocabulary quickly and without much headache:


** -proof **
防水 bou sui - water proof [防水靴 bou sui kutsu - water-proof shoes; 防水コート bou sui ko-to -rain coat]
防音 bou on - soundproofing [防音室 bou on shitsu - soundproof room]
防犯 bou han - prevention of crime; crime prevention [crime-proof]
防火 bou ka - fire proof
防災 bou sai - protection against (natural) disasters
防疫 bou eki - prevention of epidemics, plagues [epidemic-proof]

Then we have a few examples that appear to mean the opposite of -proof. Whereas above 防 (-proof) was added to the undesirable thing it should prevent, the following seem to have 防 to compliment that meaning:
防止 bou shi - prevention [止 means to stop]
防戦 bou sen - a defensive battle [戦 means war, battle]
防衛 bou ei - defense [衛 actually means defense]