Meaning

noun the savage and excessive killing of many people

verb kill a large number of people indiscriminately

origin1580, from Middle French massacre, from Old French macacre, marcacre, macecre, macecle (“slaughterhouse, butchery”), usually thought to be deverbal from Old French macecrer, macecler (“to slaughter”), though the noun seems to be attested somewhat earlier. It is also found in Medieval Latin mazacrium (“massacre, slaughter, killing”, also “the head of a newly killed stag”). Further origin disputed:…

Etymology from Wiktionary, CC BY-SA 3.0