A.joint, Emp.17.22, etc.; “ἄρθρων πόνοι” Hp. Aph.3.31, al.; “ἅπαν κατ᾽ ἄρθρον” S.Tr.769; κρᾶτα καὶ ἄρθρα the head and joints of the neck, Id.Ph.1208 (lyr., codd.); esp. the socket of the ankle-joint, “ὁ ἀστράγαλος ἐξεχώρησε ἐκ τῶν ἄ.” Hdt.3.129; in Hp.Art. I, al., ball of a joint, opp. socket (κοτύλη), cf. Gal.18(2).487 (but socket in Hp.Loc.Hom.6); “μάρψας ποδός νιν ἄρθρον ᾗ λυγίζεται” S.Tr.779, cf. Ph.1202 (lyr.).
2. generally, of limbs, etc., esp. in pl., ἄ. ποδοῖν the ankles, Id.OT718, cf. 1032; of the legs, “βραδύπουν ἤλυσιν ἄρθρων προτιθεῖσα” E.Hec.67 (lyr.); ἄ. τῶν κύκλων eyes, S.OT1270; ἄ. στόματος the mouth, E.Cyc.625; “θέναρ διῃρημένον ἄρθροις” lines, Arist.HA493b33; τὰ ἄ. alone, genitals, Hdt.3.87, 4.2, Arist.HA504b23, al; τὰ ἐντὸς ἄ. the internal organs, Mnesith. ap. Orib.8.38.7: metaph., “ἄ. τᾶν φρενῶν” Epich.250: in sg., ἄρθρον τῆς φωνῆς vocal articulation, Arist.HA536a3.
II. Gramm., connecting word, Id.Po.1457a6; esp. of the article, Id.Rh.Al.1435a35, Chrysipp.Stoic.2.45, D.H.Th.37, al.