MUSCLES OF RESPIRATION. When the diaphragm contracts in inspiration, initially the lower ribs are fixed and the dome of the diaphragm descends, thus increasing the vertical diameter of thorax.
arrearage. 1  the state or condition of being in arrears. 2  Often, arrearages. arrears; amount or amounts overdue. 3  Archaic. a thing or part kept in reserve.
proofread-read for errors; I should proofread my manuscripts. proof. insure, see to it, ensure, ascertain, check, assure, control, see-be careful or certain to do something; make certain of something; He verified that the valves were closed; See that the curtains are closed; control the quality of the product.