Resting one or both knees on the ground. In other words, knees on the ground, butt off the ground.
Not to be confused with squatting, which is when the knees are off the ground, or all fours, which is when both the hands and knees are on the ground, or with seiza, which is when the legs are completely folded and the butt is sitting on the feet.
The following tags are aliased to this tag: on_knees (learn more).