Decimate

[Sarah]

To select by lot and punish with death every tenth man
of; as, to decimate a regiment as a punishment for mutiny.

[Sonia]

A frequently misused word.
[Decimate] literally means to reduce something by a tenth, but many people use it instead to mean totally destroy. The word [obliterate] would be a better choice than [decimate].
Decimate comes from the root deci- which can be found in other words involving ten, [decimal] for example.

[Jason Yan]

the verb to decimate comes from the root of the Latin word for ten. Obvious enough, but the use gets more interesting. The verb To decimate is synonymous with to destroy and may be used to talk about a great reduction, loss, etc. Decimation was used as a Roman military strategy, as punishment for a severe crime, typically [rebellion] or desertion, the army would be forcibly [lined up], and every tenth person would be killed. The form of group punishment based on the [number ten] is an adequate enough explanation for the origin of the word. Today, the word can be used in a less mathematical context, and still be grammatically correct, though its still an intense verb.

[Ernesto]

Kill, destroy, or remove a large proportion of.

[Merna]

An incorrectly overused word often heard when the speaker actually means to say [devastate], possibly due to the fact that the two words sound quite similar. Decimate means to [reduce] (by some portion), so it more accurately represents loss or [attrition], especially in reference to a given population.