Boyd’s Bible Dictionary:
(Persian “dara,” king). (1) Darius the Mede (Dan. 5:31; 6; 9:1; 11:1). Captured Babylon from Belshazzar, B. C. 538. (2) Darius Hystaspes, King of Persia, B. C. 521-486. He restored the captive Jews (Ezra 4:5,24; 6:14-15; Hag. 1:1,15; Zech. 1:1,7; 7:1). (3) Darius the Persian (Neh. 12:22). Darius Codomanus, B. C. 336-330, last king of Persia.
Concise Bible Dictionary:
1. DARIUS THE MEDE, son of Ahasuerus. He was probably the Astyages of the historians. Some supposed “Darius” to be a title and not a name, but the name has been found on the monuments. On the death of Belshazzar he possessed Babylon, being about 62 years of age (B.C. 538-6) (Dan. 5:31; Dan. 6:9-28; Dan. 9:1; Dan. 11:1). See BABYLON and DANIEL.
2. DARIUS HYSTASPIS, king of Persia (B.C. 521-485). He confirmed the decree of Cyrus in favor of the Jews, and the building of the temple (Ezra 4:5,24; Ezra 5:5-7; Ezra 6:1-15; Hag. 1:1,15; Hag. 2:10; Zech. 1:1, 7; Zech. 7:1. To this king is ascribed the consolidating of the empire of Persia.
3. DARIUS THE PERSIAN. Darius Ochus (Nothus) of the historians (B.C. 424-405). Only mentioned in Nehemiah 12:22. For a list of the Persian kings see PERSIA.
Strong’s Dictionary of Hebrew Words:
Transliteration:
Dar`yavesh
Phonic:
daw-reh-yaw-vaysh’
Meaning:
of Persian origin; Darejavesh, a title (rather than name) of several Persian kings
Jackson’s Dictionary of Scripture Proper Names:
investigation: the dwelling will be full of heaviness
Potts’ Bible Proper Names:
He who enforces and inquires; coercer; conservator:―the name of several kings of Media and Persia, Ezra 4:5. {Coercitor}