muscular atrophy skeletal muscle atrophy MP:0009417 MPheno.ontology acquired diminution of the size of skeletal muscle tissue associated with wasting as from death and reabsorbtion of cells, diminished cellular proliferation, decreased cellular volume, pressure, ischemia, malnutrition, reduced function or malfunction, or hormonal changes; occurs with age, immobilization, weightlessness, malnutrition or denervation decreased skeletal muscle size