osteopenia

n.
A generalized reduction in bone mass that is less severe than that resulting from osteoporosis, caused by the resorption of bone at a rate that exceeds bone synthesis.

(os′tē-ōpē′n-ə)
n

The deterioration of bone density, decrease of calcification, or insufficient synthesis of uncalcified bone material.

A progressive condition characterized by reduced bone mineral density without the presence of a fracture, but which predisposes the individual to osteoporosis.

(ŏs'tē-ə-pē'nē-ə)
n.

A condition of bone in which decreased calcification, decreased density, or reduced mass occurs.

Reduced bone mass due to a decrease in the rate of osteoid synthesis to a level insufficient to compensate for normal bone lysis. The term is also used to refer to any decrease in bone mass below the normal.