Overwhelm and its rare synonym whelm have both been around since the Middle Ages, but underwhelm is a 20th-century coinage. Both overwhelm and whelm are derived from the Middle English whelmen, which is perhaps an alteration of whelven ("to turn over" or "to cover up"). Underwhelm is a playful overturning of overwhelm well suited for describing the unimpressive. More than one person claims the distinction of having invented underwhelm; several sources attribute it to the playwright George S. Kaufman, but sports columnist Red Smith is quoted as believing he coined the word himself, and still other sources cite other potential creators. Chances are that the word was in fact coined by more than one inventive writer.