Abbott-Smith Manual Greek Lexicon
διάδημα (G1238)
3 διάδημα , -τος, τό ( διαδέω , to bind round ), [in LXX for כֶּתֶר (as Es 1:11 ), etc. ;] the band round the τιάρα of a Persian king; a diadem , the badge of royalty: Re 12:3 13:1 19:12 .† SYN. : στέφανος , the badge of "victory, of valour, of nuptial joy, of festal gladness " (but v. M, Th. , i, 2 19 ; cf. DB , i, 530, 604).
G. Abbott-Smith, A Manual Greek Lexicon of the New Testament (1922) — public domain