The headword is a rare masculine noun in the nominative singular (LSJ s.v.). The entry has probably been generated by the quotation given, which contains the only appearance of the headword (accusative case) outside lexicography.
[1] The glossing phrase is in the neuter singular. The same gloss is given by John Philoponus, Differences s.v. ku/rtos (basket or weel); and see also Eudemus.
[2] Polybius fr. 65 Büttner-Wobst (unplaced). [In her critical apparatus Adler notes that ms F omitted the quotation, but retained Polybius as the source of the lemma, while ms A omitted both; also that Kuster deleted the words tw=n e)xqrw=n: the enemy.]