To knot or twist something.
To snarl or growl; to gnar.
Gnarled, knotty, twisted.
A knot in wood; a large or hard knot, or a protuberance with twisted grain, on a tree.
Something resembling a knot in wood, such as in stone or limbs.
To squeeze (wet clothing or cloth), either by twisting with one's hands, or by passing it through a wringer, to remove the water.
To push (an aircraft) to its performance limits; to push the envelope.
To force someone to give (something), usually truth, or money.