os·te·o·po·ro·sis 
(ŏs′tē-ō-pə-rōsĭs)
(ŏs′tē-ō-pə-rōsĭs)n. pl. os·te·o·po·ro·ses (-sēz)
A disease characterized by a decrease in bone mass and density, occurring especially in postmenopausal women, resulting in a predisposition to fractures.
[New Latin : OSTEO- + Greek poros, passage, pore; see PORE2 + -OSIS.]
os′te·o·po·rotic (-rŏtĭk) adj.