on the safe side
用作副词及形容词的意思:可靠地(的)或安全地 (的)
用法及例句:It didn't look like rain, but she took her umbrella to be on the safe side.天不像会下雨,但她仍带了雨伞以防万一。
英汉词典参考:
on
the
safe
side