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.
Legal Definition of arrear. 1  1a : the condition of being behind in one's duties or especially financial obligations âusually used in plural in arrears with the rent b : the condition of being due at the end of a term rather than the beginning âusually used in plural mortgage payments are made in arrears.