Origin: 1590–1600; < L
decimātus, ptp. of
decimāre to punish every tenth man chosen by lot, v. deriv. of
decimus tenth, deriv. of
decem ten; see
ate1 
Related forms: dec⋅i⋅ma⋅tion, noun
dec⋅i⋅ma⋅tor, noun
Usage note:
The earliest English sense of decimate is “to select by lot and execute every tenth soldier of (a unit).” The extended sense “destroy a great number or proportion of” developed in the 19th century: Cholera decimated the urban population. Because the etymological sense of one-tenth remains to some extent, decimate is not ordinarily used with exact fractions or percentages: Drought has destroyed (not decimated) nearly 80 percent of the cattle.
[des-uh-meyt] 