köken: Borrowed from Late Latin pentagōnum, from Ancient Greek πεντάγωνον (pentágōnon, “pentagon”), neuter form of πεντάγωνος (pentágōnos, “five-angled”). Equivalent to penta- + -gono.
köken: From Late Latin pentagōnum, from Ancient Greek πεντάγωνον (pentágōnon, “pentagon”), neuter form of πεντάγωνος (pentágōnos, “five-angled”). By surface analysis, penta- + -gono.
köken: Substantivized neuter adjective πεντάγωνος by ellipsis of the noun σχήμα (schíma, “shape”). Morphologically from πεντα- (“penta-”) + -γωνο (“-gon”).