The first part, glam, means "barbaric speech", and is an expansion of lam, "tongue, language". An individual within the group is referred to as a glamog, and glam appears in Glamdring. The second element, hoth is a common suffix to denote a collection of people.
Throughout history, populations have always considered the languages of other peoples inferior, or uncouth to the ears. The term "Barbarian" originally ment "brabbler". Simlarly, Germany is called "Land of the Mute", "land of those who do not speak our tongue" in some Slavic countries. A similar pattern is found in Adûnaic, where the word for "shout" (rûkh) is related to the words for "Orc", uruk.