Liddell-Scott-Jones

ἄρθρον (arthron) articulation ^G:N-N

ἄρθρον, τό,

(ἀραρίσκω) joint, [ἄρθρον 5th c.BC: Sophocles Tragicus “Trachiniae” 769">Refs 5th c.BC+]; κρᾶτα καὶ ἄρθρα the head and joints of the neck, [Refs]; especially the socket of the ankle-joint, ὁ ἀστράγαλος ἐξεχώρησε ἐκ τῶν ἄ.[Refs 5th c.BC+], ball of a joint, opposed to socket (κοτύλη),[Refs 2nd c.AD+] (but socket in [ἄρθρον ᾗ λυγίζεται 5th c.BC: Sophocles Tragicus “Trachiniae” 779, compare “Ph.” 1202 (Lyric poetry). ">Refs 5th c.BC+]

__2 generally, of limbs, etc., especially in plural, ἄ. ποδοῖν the ankles, [Refs]; of the legs, βραδύπουν ἤλυσιν ἄρθρων προτιθεῖσα[Refs 5th c.BC+]; ἄ. τῶν κύκλων eyes, [Refs 5th c.BC+]; ἄ. στόματος the mouth, [Refs 5th c.BC+]lines, [Refs 4th c.BC+]; τὰ ἄ. alone, genitals, [Refs 5th c.BC+] the internal organs, Mnesith. cited in [ἄρθρον τῆς φωνῆς">Refs 5th c.BC+] vocal articulation, [Refs 4th c.BC+]
__II Grammars, connecting word, [Refs]; especially of the article, [Refs 3rd c.BC+]