διάστασις

διάστασις, εως, ἡ, (διΐστημι) A. parting, separation (opp. ἕνωσις, Dam. Pr. 273), ὀρέων Hdt. 7.129; ὀστέων Hp. Art. 20, cf. Gal. 19.461; φάραγγες καὶ δ. τῆς γῆς fissures, Arist. Mete. 350b36; breach in a barrier, Ph. Bel. 98.31; opening, τῆς γένυος Aret. CD 1.3. b. κεφαλῆς δ. splitting headache, ibid. (pl.), v.l. in Pl. R. 407c. c. distension, Arist. PA 681b24; φλεβῶν Aret. SA 2.2. d. δ. κενεή retching, ib. 2.7. e. = διαστολή, of the pulse, Zeno ap.Gal. 8.736. f. expansion of air, opp. πίλησις, Ph. Bel. 77.23. 2. setting at variance, τοῖς νέοις ἐς τοὺς πρεσβυτέρους Th. 6.18, cf. Plu. Cor. 16; cause of breach, Arist. Pol. 1303b15. b. contrasting, Pl. R. 360e. 3. difference, contrast, Arist. Cael. 312a13. 4. disagreement, δ. ἢ στάσις Pl. Lg. 744d, cf. Arist. Pol. 1296a8, 1300b37. 5. divorce, Plu. Aem. 5, etc. II. Gramm., of vowels, διαίρεσις κατὰ διάστασιν (as in πάϊς) A.D. Pron. 87.4. b. τὰ κατὰ δ. forms written as two words, e.g. ἐμέθεν αὐτῆς ib.114.11. III. interval, Pl. Ti. 36a, etc.; in Music, Aristox. Harm.p.4 M., al.; of space, extension, Arist. Top. 142b5, al.; dimension, τὰς αὐτὰς διαστάσεις εἰς βάθος εἰληφός Epicur. Nat. 2.7, cf. Gal. 11.503, S.E. M. 3.19; ἡ δ. ἡ τριχῇ tridimensionality, Plot. 1.2.6, cf. 6.6.17, Porph. Sent. 35, Dam. Pr. 375. IV. = διακόσμησις, Antipho Soph. 23. (Freq. confused with διάτασις, wh. shd. perh. be read in 1.1.b,c,d.)