(2021-09-13, 12:24)N. W. Perry Wrote: One name I forgot about that's often used for this underside feature is "post". That goes well with the equivalently-functioning "tube", and also fits the ability to be inserted into a hollow stud. And the common feature of tubes and posts is, of course, to provide clutch by gripping the spaces between studs, while secondarily allowing an offset construction by inserting a stud into a tube, or a post into a stud.
"Post" feels like a good term for this - it has an architectural context for "holding stuff up" and is complementary to Tube. Thanks for the suggestion!