mid-13c., derthe "scarcity" (originally used of famines, when food was costly because scarce; extended to other situations of scarcity from early 14c.), abstract noun formed from root of Old English deore "precious, costly" (see dear) + abstract noun suffix -th(2). Common Germanic formation, though not always with the same sense (cognates: Old Saxon diurtha "splendor, glory, love," Middle Dutch dierte, Dutch duurte, Old High German tiurida "glory").