a·tre·sia 
(ə-trēzhə, -zhē-ə)
(ə-trēzhə, -zhē-ə)n.
1. The absence or closure of a normal body orifice or tubular passage such as the anus, intestine, or external ear canal.
2. The degeneration and resorption of one or more ovarian follicles before a state of maturity has been reached.
[New Latin atrēsia : Greek a-, not, without; see A-1 + Greek trēsis, perforation, orifice; see terə-1 in the Appendix of Indo-European roots.]
a·tre·sic (-zĭk, -sĭk) adj.