Merriam-Webster Collegiate Dictionary - exergue

 noun  Etymology: French, from New Latin exergum, from Greek ex out of + ergon work  Date: 1697 a space on a coin, token, or medal usually on the reverse below the central part of the design EXERT  transitive verb  Etymology: Latin exsertus, past participle of exserere to thrust out, from ex- + serere to join — more at series  Date: circa 1630  1.  a. to put forth (as strength) the force is ~ed sideways  b. to put (oneself) into action or to tiring effort won't have to ~ himself moving the table  2. to bring to bear especially with sustained effort or lasting effect ~ed a bad influence on his students  3. employ, wield ~ed her leadership abilities intelligently