The Collaborative International Dictionary of English v.0.48:
Phimosis \Phi*mo"sis\, n. [NL., fr. Gr. ? a muzzling, fr. ? muzzle.] (Med.) A condition of the penis in which the prepuce can not be drawn back so as to uncover the glans penis. [1913 Webster]WordNet (r) 3.0 (2006):
phimosis n 1: an abnormal tightness of the foreskin preventing retraction over the glans