plimsoll /ˈplɪmsoʊl/ noun2 •(UK, Ireland) A rubber-soled lace-up canvas shoe for sports or onboard ships; a precursor of trainers.“Yes, there are two distinct sets of footprints, both wearing rubber shoes—one I think ordinary plimsolls, the other goloshes,” replied the sergeant. — 1928 •The plimsoll symbol ⦵ (or o) that is used as a superscript in the notation of thermodynamics to indicate an arbitrarily chosen non-zero reference point. formsplimsolls
