Thinking phonetic similarities between words prove origin or relation is a common mistake of amateur etymologists, as in this junk etymology, where the author, a known crank who favors simplistic and unverified Irish origins for a variety of English words—because he thinks American and English lexicographers have an anti-Irish bias—posits that bunkum comes from a buanchumadh, an Irish-Gaelic word he says means “perpetual invention, endless composition (of a story, poem, or song), a long made-up story, fig. a shaggy dog tale.” Of course, he provides no written citations of the word in English-language contexts. He’s got bupkus to prove his claim.
The author, Daniel Cassidy, used to post his rubbish to the email list of the American Dialect Society, but when his rickety logic and dubious scholarship couldn’t withstand the scrutiny of interested scholars and dilettantes, he took his quackery other places to people who don’t know any better.
