τέρθριος
From LSJ
τά δέ ἄνευ συμπλοκῆς, οἷον ἄνθρωπος, βοῦς, τρέχει, νικᾷ → and the simple forms of speech, for example: 'man', 'ox', 'runs', 'wins'
English (LSJ)
ὁ,
A rope from the end of a sail-yard (τέρθρον), used for reefing, Ar.Eq.440, cf. Sch. ad loc.; τ. κάλοι Erot., Gal.19.145. II τερθρία πνοή, cited from S. (Fr.333) in EM753.7, is there expld. by ὀπισθία, a stern wind, but perh. rather a stiff gale requiring the use of τέρθριοι.