This word has been used by clueless people for most of my life. I do think the Balloon-Head-in-Chief would love to use it on the American people, at least those of us who know he is trying to destroy the country and may well succeed.
I believe the Romans used the technique a couple of millennia ago to pacify groups and regions. It also helped control population growth, roughly ten percent at a time.
Decimation was the way Rome punished army units for crimes like cowardice. One soldier out of ten would be randomly killed.