knee-deep

See also: kneedeep

English

From Middle English kne-depe; equivalent to knee +‎ deep.

knee-deep (not comparable)

Reaching up to the knees.
- 1831, L[etitia] E[lizabeth] L[andon], Romance and Reality. […], volume III, London: Henry Colburn and Richard Bentley, […], OCLC 24531354, page 277:
  High above stood the ash-tree, its boughs covered with the toy-like bunches called "locks and keys;" and beyond spread the meadows, knee-deep with the verdant grass.
Submerged to the knees.
- 1898, H.G. Wells, The War of the Worlds, London: William Heinemann, page 241:
  This gave me a hint, and I went knee-deep, and sometimes neck-deep, in the Red Weed. The density of the weed gave me a reassuring sense of hiding.
(figuratively, by extension) Deeply involved in something, or preoccupied with something.

reaching up to the knees

deeply involved