The Collaborative International Dictionary of English v.0.48:
Penology \Pe*nol"o*gy\, n. [Gr. poinh`, or L. poena, punishment + -logy.] The science or art of punishment. [Written also p[oe]nology.] [1913 Webster]WordNet (r) 3.0 (2006):
penology n 1: the branch of criminology concerned with prison management and prisoner rehabilitation [syn: penology, poenology]