definition of
IV

[1] #1 IV n. [four, 4, 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, iv] being one more than three. wn

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