n. 滚木材, 相互吹棒, 水上踩滚木

Logrolling \Log"roll`ing\, n.
1. (Logging) The act or process of rolling logs from the
place where they were felled to the stream which floats
them to the sawmill or to market. In this labor
neighboring camps of loggers combine to assist each other
in turn. --Longfellow. [U.S.]

2. Hence: A combining or mutual agreement in which one
politician supports or assists another in consideration of
receiving assistance in return; wheeling and dealing; --
sometimes used of a disreputable mode of accomplishing
political schemes or ends. [Cant, U.S.]