To "decimate" means to:

To "decimate" means to kill in large numbers, originating from a practice in ancient Rome where one in every ten soldiers was executed as a punishment for the entire group. This historically denotes significant destruction or loss, especially in a military context. The term has since evolved in modern usage to refer generally to a substantial reduction or devastation of a population or group. Therefore, the essence of the word captures the idea of a considerable decrease, particularly through lethal means, which aligns perfectly with the provided definition of killing in large numbers.