repay

Etymology

From Old French repaier (“to pay back”), from re- + paiier (“to pay”), from Latin pācāre (“to settle, to make peaceful”), from pāx (“peace”) + -ō (“forming verbs”). Equivalent to re- + pay. Cognate with repacify and French repayer (“to pay again”).

verb

1. Synonym of pay back in all senses.
   I finally repaid my student loans, just before sending my kids to college.
   On the results of the Kent Coast electrification, which is known to be repaying so far a satisfactory return on the investment in it, a Waterloo-Bournemouth scheme shows reasonable financial promise. 1962 April, “Talking of Trains: Short-sighted approach to profits?”, in Modern Railways, page 219
2. (transitive) To make worthwhile; to yield a result worth the effort; to pay off.
   The possible importance of excessive androgen secretion and the ingestion of agents such as the fluorenamines may repay further investigation. 2013, M. Pavone-MacAluso, Testicular Cancer and Other Tumors of the Genitourinary Tract, page 517