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.
arÂ·biÂ·trage. n. The simultaneous purchase and sale of equivalent assets or of the same asset in multiple markets in order to exploit a temporary discrepancy in prices. intr.v. arÂ·biÂ·traged, arÂ·biÂ·tragÂ·ing, arÂ·biÂ·tragÂ·es. To be involved in arbitrage.erb. 1. arbitrage-practice arbitrage, as in the stock market. commerce, commercialism, mercantilism-transactions (sales and purchases) having the objective of supplying commodities (goods and services). merchandise, trade-engage in the trade of; he is merchandising telephone sets.