Q. Dear Editor: Do you believe that number matters? In the following sentence about a company that makes washboards, is it “Today, a half dozen women continue building a household anachronism that’s seldom seen anymore” or “Today, a half dozen women continue building household anachronisms that are seldom seen anymore”? Thank you.
A. Number does matter, but the problem here is that washboards (plural) are an anachronism (singular). To say that they are anachronisms is correct as well, but in the same way that you would say these women (collectively) are doing a job or creating a product or pursuing a dream, it’s idiomatic to say that they are building an anachronism. If you use the plural, it loses the collective sense, which in some contexts is accurate, but I think not in this one.