There are two common words used for hell. Hades and Hell.
Hades. The region of departed spirits of the lost (but including the blessed dead in periods preceeding the Ascention of Christ). It has been thought by some that the word etymologically meant the unseen (from a, negative, and eido, to see), but this derivation is questionable; a more probable derivation is from hado, signifying all-receiving. It corresponds to "Sheol" in the O.T. In the A.V. of the O.T. and N.T., it has been unhappily rendered "Hell," e.g., Psa. 16:10; or "the grave," e.g. Gen. 37:35; or "the pit," Num. 16:30, 33; in the N.T. the Revisers have always used the rendering "Hades;" in the O.T. they have not been uniform in the translation, e.g., in Isa. 14:15, "hell" (marg., "Sheol"); usually they have "Sheol" in the text and "the grave" in the margin. It never denotes the grave, nor is it the permanent region of the lost; in point of time it is, for such, intermediate between decease and the doom of Gehenna. For the condition, see Luke 16:23-31.
The word is used four times in the Gospels, and always by the Lord, Matt. 11:23; 16:18; Luke 10:15; 16:23; it is used with refrence to the soul of Christ, Acts 2:27, 31; Christ declares that He has the keys of it, Rev. 1:18; In Rev. 6:8 it is personified, with the signification of the temporary destiny of the doomed; it is to give up those who are therein, 20:13, and is to be cast into the lake of fire. ver. 14.
Note: In I Cor. 15:55 the most authenic mss. have thanalos, death, in the 2nd part of the verse, instead of Hades, which the A.V. wrongly renders "grave" ("hell" in the marg.).
Hell. Geenna represents the Hebrew Ge-Hinnom (the Valley of Tophet) and a corresponding Aramaic word; it is found twelve times in the N.T., eleven of which are in the Synoptists, in every instance as uttered by the Lord Himself. He who says to his brother, Thou fool, will be in danger of "the hell of fire," Matt. 5:22; it is better to pluck out (a metaphorical description of irrevocable law) an eye that causes its possessor to stumble, than that his "whole body be cast into hell," ver. 29; similarily with the hand, ver. 30; in Matt. 18:8, 9, the admonitions are repeated, with an additional mention of the foot; here, too, the warning concerns the person himself (for which obviously the "body" stands in chap. 5); in ver, 8, "the eternal fire" is mentioned as the doom, the character of the region standing for the region itself, the two being combined in the phrase "the hell of fire," ver. 9. To the passage in Matt. 18, that in Mark 9:43-47, is parallel; here to the word "hell" are applied the extended descriptions "the unquenchable fire" and "where their worm dieth not and the fire is not quenched."
That God, "after He hath killed, hath power to cast into hell," is assigned as a reason why He should be feared with the fear that keeps from evil doing, Luke 12:5; the parallel passage to this in Matt. 10:28 declares not the casting in, but the doom which follows, namely, the destruction (not the loss of being, but of well-being) of "both soul and body."
In Matt. 23 the Lord denounces the Scribes and Pharisees, who in proselytizing a person "make him two-fold more a son of hell" than themselves (ver. 15), the phrase here being expressive of moral characteristics, and declares the impossibility of their escaping" the judgment of hell." ver. 33. In Jas. 3:6 hell is described as the source of the evil done by misuse of the tongue; here the word stands for the powers of darkness whose characteristics and destiny are those of hell.
For terms descriptive of hell, see e.g. Matt. 13:42; 25:46; Phil. 3:19; II Thess. 1:9; Heb. 10:39; II Pet. 2:17; Jude 13; Rev. 2:1; 19:20; 20:6, 10, 14; 21:8.