Worth  —predic. Adj. (used like a preposition) 1 of a value equivalent to (is worth £50; is worth very little). 2 such as to justify or repay (worth doing; not worth the trouble). 3 possessing or having property amounting to (is worth a million pounds). —n. 1 what a person or thing is worth; the (usu. High) merit of (of great worth). 2 equivalent of money in a commodity (ten pounds' worth of petrol).  for all one is worth colloq. With one's utmost efforts. For what it is worth without a guarantee of its truth or value. Worth it colloq. Worth while. Worth one's salt see *salt. Worth one's weight in gold see *weight. Worth while (or one's while) see *while. [old english]