Word Origin & History
decimation
1549, from L.L. decimationem, from L. decimare "the removal or destruction of one-tenth," from decem "ten." Killing one in ten, chosen by lots, from a rebellious city or a mutinous army was a common punishment in classical times. Earliest sense in Eng. was of a tithe; decimate has been used (incorrectly, to the irritation of pedants) since 1663 for "destroy a large portion of."