Destroying or killing a large part of the population (literally every tenth person as chosen by lot).

Roget 103: fewness etc. adj.; paucity, small number; small quantity etc. 32; rarity; infrequency etc. 137; handful, maniple; minority; exiguity.    [Diminution of number] reduction; weeding etc. v.; elimination, sarculation^†, decimation; eradication.    ... meer laten zien

Roget 99: division by five etc. 98; quinquesection &c.; decimation; fifth etc.

Nederlands: slachting
Pools: decymacja