Accreistre

Accrue - intr. v. -crued, -cruing, -crues. 1. To come to someone or something as a gain, addition, or increment. 2. To increase or accumulate, as by natural growth, or as interest on capital. [ Middle English acrewen, probably from Old French accreue, growth, from the past participle of accreistre, to increase, from Latin accrescere : ad-, in addition + crescere, to grow.]

The American Heritage Dictionary of the English Language (1971). William Morris, Editor. New York: American Heritage Publishing Co., Inc.