Decimate v. t. : To take the tenth part of; to tithe.

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

Decimate v. t. : To destroy a considerable part of; as, to decimate an army in battle; to decimate a people by disease.

Example:
How does Decimate work? MTG Magic the Gathering Question?

Taxonomy
Dictionary, mate, proportion, tenth person, Synonyms, decimus, killing, deriv, great number, population, decem, free online English dictionary, word origin, Usage note, Panel, accepts, Houghton Mifflin Company, dictionary results.

Defination from the web:
Decimate - Definition of Decimate at Dictionary.com a free online dictionary with pronunciation, synonyms, and translation of Decimate. Word of the Day and Crossword Puzzles. ... The earliest English sense of decimate is "to select by lot and execute every tenth soldier of (a unit) ...