divers sorts of flies, swarm

Boyd’s Bible Dictionary:

Of many varieties in East, and very noisome
(Ex. 8:21-3121Else, if thou wilt not let my people go, behold, I will send swarms of flies upon thee, and upon thy servants, and upon thy people, and into thy houses: and the houses of the Egyptians shall be full of swarms of flies, and also the ground whereon they are. 22And I will sever in that day the land of Goshen, in which my people dwell, that no swarms of flies shall be there; to the end thou mayest know that I am the Lord in the midst of the earth. 23And I will put a division between my people and thy people: to morrow shall this sign be. 24And the Lord did so; and there came a grievous swarm of flies into the house of Pharaoh, and into his servants' houses, and into all the land of Egypt: the land was corrupted by reason of the swarm of flies. 25And Pharaoh called for Moses and for Aaron, and said, Go ye, sacrifice to your God in the land. 26And Moses said, It is not meet so to do; for we shall sacrifice the abomination of the Egyptians to the Lord our God: lo, shall we sacrifice the abomination of the Egyptians before their eyes, and will they not stone us? 27We will go three days' journey into the wilderness, and sacrifice to the Lord our God, as he shall command us. 28And Pharaoh said, I will let you go, that ye may sacrifice to the Lord your God in the wilderness; only ye shall not go very far away: entreat for me. 29And Moses said, Behold, I go out from thee, and I will entreat the Lord that the swarms of flies may depart from Pharaoh, from his servants, and from his people, to morrow: but let not Pharaoh deal deceitfully any more in not letting the people go to sacrifice to the Lord. 30And Moses went out from Pharaoh, and entreated the Lord. 31And the Lord did according to the word of Moses; and he removed the swarms of flies from Pharaoh, from his servants, and from his people; there remained not one. (Exodus 8:21‑31); Psa. 78:4545He sent divers sorts of flies among them, which devoured them; and frogs, which destroyed them. (Psalm 78:45); Eccl. 10:11Dead flies cause the ointment of the apothecary to send forth a stinking savor: so doth a little folly him that is in reputation for wisdom and honor. (Ecclesiastes 10:1); Isa. 7:1818And it shall come to pass in that day, that the Lord shall hiss for the fly that is in the uttermost part of the rivers of Egypt, and for the bee that is in the land of Assyria. (Isaiah 7:18)).

Concise Bible Dictionary:

 
Fly
arob, the dog-fly. In Psalm 78:4545He sent divers sorts of flies among them, which devoured them; and frogs, which destroyed them. (Psalm 78:45), and Psalm 105:3131He spake, and there came divers sorts of flies, and lice in all their coasts. (Psalm 105:31), this word is rendered in the A.V. “divers sorts of flies,” referring to one of the plagues in Egypt, and is translated “swarms [of flies]” in Exodus 8:21-3121Else, if thou wilt not let my people go, behold, I will send swarms of flies upon thee, and upon thy servants, and upon thy people, and into thy houses: and the houses of the Egyptians shall be full of swarms of flies, and also the ground whereon they are. 22And I will sever in that day the land of Goshen, in which my people dwell, that no swarms of flies shall be there; to the end thou mayest know that I am the Lord in the midst of the earth. 23And I will put a division between my people and thy people: to morrow shall this sign be. 24And the Lord did so; and there came a grievous swarm of flies into the house of Pharaoh, and into his servants' houses, and into all the land of Egypt: the land was corrupted by reason of the swarm of flies. 25And Pharaoh called for Moses and for Aaron, and said, Go ye, sacrifice to your God in the land. 26And Moses said, It is not meet so to do; for we shall sacrifice the abomination of the Egyptians to the Lord our God: lo, shall we sacrifice the abomination of the Egyptians before their eyes, and will they not stone us? 27We will go three days' journey into the wilderness, and sacrifice to the Lord our God, as he shall command us. 28And Pharaoh said, I will let you go, that ye may sacrifice to the Lord your God in the wilderness; only ye shall not go very far away: entreat for me. 29And Moses said, Behold, I go out from thee, and I will entreat the Lord that the swarms of flies may depart from Pharaoh, from his servants, and from his people, to morrow: but let not Pharaoh deal deceitfully any more in not letting the people go to sacrifice to the Lord. 30And Moses went out from Pharaoh, and entreated the Lord. 31And the Lord did according to the word of Moses; and he removed the swarms of flies from Pharaoh, from his servants, and from his people; there remained not one. (Exodus 8:21‑31): so that more than one kind may have been meant.
 
Dog or Stable Fly – Stomoxys Calcitrans
2. zebub, supposed to be the gad-fly. They fell into the ointment and spoiled it (Eccl. 10:11Dead flies cause the ointment of the apothecary to send forth a stinking savor: so doth a little folly him that is in reputation for wisdom and honor. (Ecclesiastes 10:1)). In the judgments of God in the days of Ahaz He hissed for the fly from the rivers of Egypt (Isa. 7:1818And it shall come to pass in that day, that the Lord shall hiss for the fly that is in the uttermost part of the rivers of Egypt, and for the bee that is in the land of Assyria. (Isaiah 7:18)). The stings of the flies in the East are very painful, and torment the animals almost to madness. The word zebub is considered to be a part of the word BAAL-ZEBUB, the idol-god of Ekron, “the lord of the fly,” who it was thought could protect persons from its bite.

Strong’s Dictionary of Hebrew Words:

Number:
6157 (find all occurrences in KJV Bible)
Transliteration:
`arob
Phonic:
aw-robe’
Meaning:
from 6148; a mosquito (from its swarming)
KJV Usage:
divers sorts of flies, swarm