GRC
Bailly
ῆς (ἡ) [ῐᾰ] empan,
mesure d’une demi-coudée, ou de trois quarts de pied, HDT.
2, 106 ; PLAT.
1 Alc. 126 c ; ARSTT.
Pol. 5, 3 ; H.A. 8, 28, 5.
Étym. probabl. pré-grec.
Bailly 2020 Hugo Chávez Gérard Gréco, André Charbonnet, Mark De Wilde, Bernard Maréchal & contributeurs / Licence Creative Commons Attribution - Pas d'Utilisation Commerciale - Pas de Modification — « CC BY-NC-ND 4.0 »
LSJ
ἡ, space one can embrace between the thumb and little finger, span (EM 647.34), as a fixed measure, = 3 παλαισταί (Hero Def. 131), first in Hdt. 2.106, Hp. Mochl. 38 (though the compd. τρισπίθαμος occurs in Hes. Op. 426); also in Pl. Alc. 1.126d, Arist. HA 606a14, Pol. 1302b38, Chrysipp. Stoic. 2.47, POxy. 669.32 (iii AD), etc. ;metaph, σ. τοῦ βίου Diogenian. 8.17.
Liddell-Scott-Jones, Greek-English Lexicon (9th ed., 1940)
Pape
ἡ, die Weite zwischen dem ausgespannten Daumen und dem kleinen Finger ; Her. 2.106 ; περὶ σπιθαμῆς καὶ πήχεως, Plat. Alc.I, 126c ; Sp.; Römisch dodrans.
Pape, Griechisch-deutsches Handwörterbuch (3. Aufl., 1914)
TBESG
the space one can span with the thumb and little finger, a span , Lat. dodrans, about 7 1/2 inches , [Herdotus Historicus (Refs 5th c.BC), Plato Philosophus (5th/4th c.BC)]
derivation uncertain (ML)
Translators Brief lexicon of Extended Strongs for Greek based on Abbot-Smith, A Manual Greek Lexicon of the New Testament (1922) (=AS), with corrections and adapted by Tyndale Scholars