互通有無 [ㄏㄨˋ ㄊㄨㄥ ㄧㄡˇ ㄨˊ; hu4 tong1 you3 wu2] mutual exchange of assistance (idiom) to benefit from each other's strengths and make up each other's shortfalls to reciprocate with material assistance scratch each other's back ◄ ►