1623, "to weigh more than," from L. pręponderare "outweigh," from prę- "before" + ponderare "to weigh" (see pound (n.1)). Meaning "to exceed in force or power" is from 1799. Preponderance is first recorded 1681, meaning "greater weight;" sense of "greater importance" is from 1780; that of "greater number" is from 1845.