[di.a.mond] n, often attrib [ME diamaunde, fr. MF diamant, fr. OF, fr. LL diamant-, diamas, alter. of L adamant-, adamas hardest metal, diamond, fr. Gk] (14c) 1 a: native crystalline carbon that is usu. nearly colorless, that when transparent and free from flaws is highly valued as a precious stone, and that is used industrially as an abrasive powder and in rock drills because of its great hardness; also: a piece of this substance b: crystallized carbon produced artificially
2: something that resembles a diamond (as in brilliance, value, or fine quality)
3: a square or rhombus-shaped figure usu. oriented with the long diagonal vertical
4. a: a playing card marked with a stylized figure of a red diamond b pl but sing or pl in constr: the suit comprising cards marked with diamonds
5: a baseball infield; also: the entire playing field
diamond vt (1751): to adorn with or as if with diamonds diamond adj (1872): of, relating to, or being a 60th or 75th anniversary or its celebration "~ jubilee"