The Collaborative International Dictionary of English v.0.48:

Hades \Ha"des\ (h[=a]"d[=e]z), n. [Gr. "a',dhs, "A'idhs; 'a
   priv. + 'idei^n to see. Cf. Un-, Wit.]
   The nether world (according to classical mythology, the abode
   of the shades, ruled over by Hades or Pluto); the invisible
   world; the grave.
   [1913 Webster]

         And death and Hades gave up the dead which were in
         them.                                    --Rev. xx. 13
                                                  (Rev. Ver.).
   [1913 Webster]

         Neither was he left in Hades, nor did his flesh see
         corruption.                              --Acts ii. 31
                                                  (Rev. Ver.).
   [1913 Webster]

         And in Hades he lifted up his eyes, being in torments.
                                                  --Luke xvi. 23
                                                  (Rev. Ver.).
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Tartarus \Tar"ta*rus\ (t[aum]r"t[.a]*r[u^]s), prop. n. [L., from
   Gr. Ta`rtaros.] (Class. Myth.)
   The infernal regions, described in the Iliad as situated as
   far below Hades as heaven is above the earth, and by later
   writers as the place of punishment for the spirits of the
   wicked. By the later poets, also, the name is often used
   synonymously with Hades, or the Lower World in general.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Hades
    n 1: (Greek mythology) the god of the underworld in ancient
         mythology; brother of Zeus and husband of Persephone [syn:
         Pluto, Hades, Aides, Aidoneus]
    2: (religion) the world of the dead; "No one goes to Hades with
       all his immense wealth"-Theognis [syn: Hell, Hades,
       infernal region, netherworld, Scheol, underworld]

Moby Thesaurus II by Grady Ward, 1.0:

112 Moby Thesaurus words for "Hades":
   Abaddon, Acheron, Agdistis, Aides, Aidoneus, Amenti, Amor,
   Aphrodite, Apollo, Apollon, Aralu, Ares, Artemis, Ate, Athena,
   Bacchus, Cerberus, Ceres, Charon, Cora, Cronus, Cupid, Cybele,
   Demeter, Despoina, Diana, Dionysus, Dis, Dis pater, Erebus, Eros,
   Gaea, Gaia, Ge, Gehenna, Great Mother, Hel, Helios, Hephaestus,
   Hera, Here, Hermes, Hestia, Hymen, Hyperion, Jove, Juno, Jupiter,
   Jupiter Fidius, Jupiter Fulgur, Jupiter Optimus Maximus,
   Jupiter Pluvius, Jupiter Tonans, Kore, Kronos, Loki, Magna Mater,
   Mars, Mercury, Minerva, Minos, Mithras, Momus, Naraka, Neptune,
   Niflheim, Niflhel, Nike, Olympians, Olympic gods, Ops, Orcus,
   Osiris, Pandemonium, Persephassa, Persephone, Phoebus,
   Phoebus Apollo, Pluto, Poseidon, Proserpina, Proserpine,
   Rhadamanthus, Rhea, Satan, Saturn, Sheol, Tartarus, Tellus, Tophet,
   Venus, Vesta, Vulcan, Zeus, avichi, hell, infernal regions,
   inferno, jahannan, limbo, lower world, nether world, perdition,
   pit of Acheron, place of torment, purgatory, shades below,
   the abyss, the bottomless pit, the grave, the pit, underworld



Easton's 1897 Bible Dictionary:

Hades
   that which is out of sight, a Greek word used to denote the
   state or place of the dead. All the dead alike go into this
   place. To be buried, to go down to the grave, to descend into
   hades, are equivalent expressions. In the LXX. this word is the
   usual rendering of the Hebrew sheol, the common receptacle of
   the departed (Gen. 42:38; Ps. 139:8; Hos. 13:14; Isa. 14:9).
   This term is of comparatively rare occurrence in the Greek New
   Testament. Our Lord speaks of Capernaum as being "brought down
   to hell" (hades), i.e., simply to the lowest debasement, (Matt.
   11:23). It is contemplated as a kind of kingdom which could
   never overturn the foundation of Christ's kingdom (16:18), i.e.,
   Christ's church can never die.

     In Luke 16:23 it is most distinctly associated with the doom
   and misery of the lost.

     In Acts 2:27-31 Peter quotes the LXX. version of Ps. 16:8-11,
   plainly for the purpose of proving our Lord's resurrection from
   the dead. David was left in the place of the dead, and his body
   saw corruption. Not so with Christ. According to ancient
   prophecy (Ps. 30:3) he was recalled to life.


The Devil's Dictionary (1881-1906):

HADES, n.  The lower world; the residence of departed spirits; the
place where the dead live.
    Among the ancients the idea of Hades was not synonymous with our
Hell, many of the most respectable men of antiquity residing there in
a very comfortable kind of way.  Indeed, the Elysian Fields themselves
were a part of Hades, though they have since been removed to Paris.
When the Jacobean version of the New Testament was in process of
evolution the pious and learned men engaged in the work insisted by a
majority vote on translating the Greek word "Aides" as "Hell"; but a
conscientious minority member secretly possessed himself of the record
and struck out the objectional word wherever he could find it.  At the
next meeting, the Bishop of Salisbury, looking over the work, suddenly
sprang to his feet and said with considerable excitement:  "Gentlemen,
somebody has been razing 'Hell' here!"  Years afterward the good
prelate's death was made sweet by the reflection that he had been the
means (under Providence) of making an important, serviceable and
immortal addition to the phraseology of the English tongue.