① 主に暴力から、誰かの身あるいは団体や組織などを守るためにそばに置いておく者。② 万が一の用心に備えて用意しておく棒。③ 心張り棒のこと。
be careful about fire; watch out for fire
better safe than sorry; one should err on the side of caution
you can never be too careful
very cautious (watchful, vigilant); taking every possible precaution
caution is the best policy