Sarah Sweeney in the Harvard Gazette:
Per-Olof Hasselgren already knew English when he arrived to the United States from Sweden 31 years ago, but in his stateside conversations, he couldn’t help but sense an owl in the moss.
Befuddled when someone remarked that something was “fishy,” Hasselgren didn’t yet grasp American slang and idiomatic expressions. “Something’s fishy” wouldn’t make much sense directly translated into Swedish, but Hasselgren eventually located its Swedish counterpart, that aforementioned head-scratching phrase involving feathered critters in a bog. (Another American expression, “to beat around the bush,” would mean to “walk like a cat around hot porridge” in Sweden.)
The George H. A. Clowes, Jr. Professor of Surgery at Harvard Medical School and surgeon at Beth Israel Deaconess Medical Center began keeping a log of these newfound turns of language as he discovered them, learning that quite a bit of American slang was based on anatomy and body parts, his specialty.
Though the surgeon spends most of his days focusing on endocrine organs, phrases like “foot in one’s mouth” and “tongue-tied” truly piqued his interest, along with the idea that expressions can be both funny and educational.