The headword is nominative plural of the noun kotulhdw/n. It is presumably quoted from somewhere -- probably Oppian, Halieutica 2.282; cf. the scholia there. Same or similar entry in other lexica (see the references at Photius kappa1021 Theodoridis) and a scholion on Homer, Odyssey 5.433 (web address 1), where the epic dative plural kotulhdono/fin occurs (cf. kappa 2167).