The headword is a masculine noun in the nominative singular; see generally LSJ s.v., and cf. tau 130, tau 133, tau 134.
The first part of the entry must be generated from somewhere -- probably Homer, Odyssey 9.219 (web address 1) and the corresponding scholion (see next note), where the nominative plural form tarsoi/ occurs. There Odysseus describes the flat baskets laden with cheeses amongst the plenitude of the Cyclops' cave; Cunliffe, p. 373.
[1] The gloss is the same form as the headword; cf. tau 38, tau 39, the nominative plural form ta/laroi at tau 138 (gloss), generally LSJ s.v., and Cunliffe, p. 372. The plural forms of the lemma and gloss are given by the scholion (= scholia vetera) to the aforementioned Homeric passage; cf. Apion Fragmenta de glossis Homericis (Ludwich), 75.101.8.
[2] The substantive here, a neuter noun in the nominative/accusative singular, is a diminutive of ka/laqos, o(, basket narrow at the base; see generally LSJ s.v., and cf. ps.-Zonaras 640.27 and 1711.8.