投鞭断流

arms enough to stem the stream (idiom); formidable army

to cast / to send / to throw oneself (into the river etc) / to seek refuge / to place oneself into the hands of

whip or lash / to flog / to whip / conductor's baton / segmented iron weapon (old) / penis (of animal, served as food)

to break / to snap / to cut off / to give up or abstain from sth / to judge / (usu. used in the negative) absolutely / definitely / decidedly

to run dry (of river)

to flow / to disseminate / to circulate or spread / to move or drift / to degenerate / to banish or send into exile / stream of water or sth resembling one / class, rate or grade