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.
This use of arrears accounting indicates that payment will be made at the end of a certain period, rather than in advance. Arrears can also refer to the fact that a business is behind on payments. In this case, the arrears amount is considered as accruing from the due date of the first missed payment. When an account is paid in arrears in this usage, each subsequent payment is applied to the oldest payment until the account is caught up..