LSJ
ἡ, and μύκλος, ὁ, black stripe on the neck and feet of the ass, acc. to Hsch. ; or a fold on its neck, acc. to EM 594.18; of the ass itself, PTeb. 409.7 (i AD, μοικ-). μύκλοι, οἱ, lewd, lustful persons, Hsch., cf. Archil. 183, Lyc. 771; μ. κάνθων, of the ass, Id. 816; cf. μυχλός.
Liddell-Scott-Jones, Greek-English Lexicon (9th ed., 1940)