The Collaborative International Dictionary of English v.0.48:

Arteriosclerosis \Ar*te`ri*o*scle*ro"sis\
   ([aum]r*t[=e]`r[i^]*[-o]*skl[-e]*r[=o]"s[i^]s), n. [NL.; Gr.
   ? artery + sclerosis.] (Med.)
   a chronic disease characterized by abnormal thickening and
   hardening of the walls of the arteries, esp. of the intima,
   occurring mostly in old age. Subtypes are distinguished, such
   as arteriolosclerosis and atherosclerosis. --
   Ar*te`ri*o*scle*rot"ic, a.
   [Webster 1913 Suppl. +PJC]

WordNet (r) 3.0 (2006):

arteriosclerosis
    n 1: sclerosis of the arterial walls [syn: arteriosclerosis,
         arterial sclerosis, hardening of the arteries,
         induration of the arteries, coronary-artery disease]