Also, wade into. Plunge into, begin or attack resolutely and energetically, as in She waded into that pile of correspondence. This idiom transfers entering water to beginning some action. [Mid-1800s]
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.