As high as would reach to the waist (of a standing person)(adjective)
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Use "waist-high" in a sentence
"In the dining room, American artist Roxy Paine's linen canvas drips with white paint near a life-size sculpture of an obese Asian man belly-flopping onto a waist-high block of faux ice."
"We cut a long, winding path through the jungle, wading through rivers that were waist-high, until we reached canyon with hundreds of slaves."
"He would already be in double figures but he shelled a waist-high chance, arguably the easiest of the eight that have gone to him at second slip, when Stephen Moore, on 43, drove loosely at Keith Barker in the first innings."