You’ve probably heard the word "gnarly" used to describe something really awesome. But gnarled means rugged, roughened and knotty, like the hands of an old wood carver, as well as the wood he carves.
We owe the adjective gnarled and other forms of the word to our friend Shakespeare, who created it in 1603. In “Measure for Measure,” he writes, “Thy sharpe and sulpherous bolt splits the un-wedgable and gnarled oak.” But gnarled didn't come into use again until the 19th century. In any case, word experts believe it's related to the Middle English word knar which means “knot in wood.”