definition of
iv

[1] #1 iv n. [four, 4, IV, tetrad, quatern, quaternion, quaternary, quaternity, quartet, quadruplet, foursome, Little Joe] the cardinal number that is the sum of three and one. wn

[2] #2 iv s. [four, 4] being one more than three. wn

[3] #3 iv n. [intravenous feeding, IV] administration of nutrients through a vein. wn