Tetrad - Definition
tetrad
n 1: the cardinal number that is the sum of three and one [syn:
four, 4, IV, tetrad, quatern, quaternion,
quaternary, quaternity, quartet, quadruplet,
foursome, Little Joe]
n 1: the cardinal number that is the sum of three and one [syn:
four, 4, IV, tetrad, quatern, quaternion,
quaternary, quaternity, quartet, quadruplet,
foursome, Little Joe]