Usage and Grammar

Q. I work for a company that produces training material for the mining industry. A machine in the mining process uses ceramic beads to grind down rocks. We refer to these ceramic beads as “grinding media.” Is it appropriate to treat “grinding media” as a singular noun? For example: “The grinding media consists of ceramic beads with a size of 3.5 to 5.0 mm.”

A. Media is not supported as a singular in this context. When media stands for “news media,” you can use the singular, but for other meanings, media is plural and takes a plural verb. What’s more, even though the words beads is plural, there is still only one grinding medium. If the medium were an uncountable item like sand, you would probably use “grinding medium” and a singular verb without a second thought. Please see CMOS 5.14 and also 5.250 (s.v. medium).