|ästēō+ noun
( plural osteoporoses )
Etymology: New Latin, from oste- + porosis
1. : a condition characterized by decrease in bone mass with decreased density and enlargement of bone spaces producing porosity and fragility and resulting from disturbances of nutrition and mineral metabolism
2. : a progressive metabolic disease of grazing animals (as horses and mules) marked by withdrawal of mineral matter from the bones causing enlargement, softening, and porosity of the bones especially of the head