Easton's Bible Dictionary (1897)
Probably connected with the Hebrew word nesher, an eagle. An Assyrian god, supposed to be that represented with the head of an eagle. Sennacherib was killed in the temple of this idol (2 Kings 19:37; Isa. 37:38).
Smith's Bible Dictionary (1863)
(the great eagle) an idol of Nineveh, in whose temple Sennacherib was worshipping when assassinated by his sons, Adrammelech and Shizrezer. (2 Kings 19:37; Isaiah 37:38) This idol is identified with the eagle-headed human figure, which is one of the most prominent on the earliest Assyrian monuments, and is always represented as contending with and conquering the lion or the bull.
Hastings' Dictionary of the Bible (1898) & Schaff's Bible Dictionary
NIS'ROCH (great eagle?), an Assyrian deity in whose temple at Nineveh Sennacherib was murdered by his sons Adrammelech and Sharezer. 2 Kgs 19:37; Isa 37:38. The etymology of the name, even the Shemitic origin of the word, is doubtful, and nothing definite is known of this deity. Some suppose him to be represented in the Assyrian tablets by a human form with the wings and head of an eagle. Others suggest that the word refers to Noah's dove, which
had been made an object of worship. Nisroch. (After Layard.)
Hitchcock's Bible Names (1869)
flight; proof; temptation; delicate