Well, what a great discussion!
According to my brief research

the word Orc (sometimes spelled Ork) originally comes from the Latin word Orcus, a title of the god Roman god Pluto, the king of the underworld. It was later used to refer to the underworld itself.
The word appears later in the germanic languages without its Latin ending, in the more familiar form of "Orc". It was then later revived by Tolkien in his fictional stories of Middle-earth as the name of a race of creatures that are often used by evil forces as soldiers.
Quote:
Originally Posted by Lith I think I read somewhere that the word "orc" pre-dated Tolkien. But yeah, it's basically the same thing as a goblin. |
Tolkien sometimes, particularly in The Hobbit, used the word "goblin" instead of "orc" (though they are completely different) to describe the same type of creature, with the smaller cave-dwelling variety that lived in the Misty Mountains being referred to as "goblin" and the larger ones elsewhere referred to as "orcs".[1]
In Tolkiens incarnation, the orcs are larger and bulkier than humans, and have a warty hide like skin. They are bred from the mud, which appears to be a direct reference to its Latin heritage.
Tolkien's own statements about the real-world origins of his use of the word "orc" are as follows:
"I originally took the word from Old English orc (Beowulf 112 orc-neas and the gloss orc = þyrs ('ogre'), heldeofol ('hell-devil'). This is supposed not to be connected with modern English orc, ork, a name applied to various sea-beasts of the dolphin order."[2]
Moving along...
Quote:
Originally Posted by Aes I did some looking into this, and it seems to have been resurrected by Tolkien from the story of Beowulf. |
The word *orcné (attested in the plural orcnéas) is indeed in the poem Beowulf. It is generally supposed to contain an element -né, cognate to Gothic naus and Old Norse nár, both meaning "corpse". The usual Old English word for "corpse" is líc, but -né appears in dryhtné "dead body of a warrior", where dryht is the name of a military unit (vaguely translated "band", "host", etc.). In *orcné, if it is to be glossed as "orcus-corpse" the meaning may be "corpse from Orcus (i.e. the underworld)" or "devil-corpse", understood as some sort of walking dead. This etymology is plausible, but remains conjectural. The word orc appears in two other locations in Beowulf, but in both cases refers to cups of precious metal found in a treasure-hoard.
Moving along again...
Quote:
Originally Posted by Fake Vencar There are so many versions of Orcs in different worlds. [sic] In the Games Workshop creations they are essentially the same height as a human, just a bit bulkier and a lot less intelligent. |
Now, I admit I do not really know much about the Games Workshop universe. However, I do know that in the Dungeons & Dragons roleplaying game, created by Gary Gygax, Orcs are a species of aggressive mammalian carnivores that band together in tribes and survive by hunting and raiding. Orcs believe that in order to survive they must expand their territory, and so they are constantly involved in wars against many enemies: humans, elves, dwarves, goblins, and other orc tribes.
Orcs vary widely in appearance as a result of frequent crossbreeding with other species. In general, they resemble primitive humans with grey-green skin covered with coarse hair. Orcs have a slightly stooped posture, a low jutting forehead, and a snout instead of a nose. Orcs have well-developed canine teeth for eating meat and short pointed ears that resemble those of a wolf. Orcish snouts and ears have a slightly pink tinge. Their eyes are human, with a reddish tint that sometimes makes them appear to glow red when they reflect dim light sources in near darkness.
Also of importance is that in the Gygax realm of D&D, orcs are only one of several types of "green skins", including trolls, goblins, and gremlins. Unique to them is that they are regenerative, ie you cant kill them by chopping off their arm, it grows back, you must kill them with fire or acid, etc...
Skipping ahead...
Quote:
Originally Posted by Culhwch I think the term 'orc' is fair game, whether or not Tolkein coined it. It has passed into the common usage, particularly in RPGs and fantasy literature - for instance Stan Nichols(?) series based around orcs, amongst many other uses... |
Now, while many various versions of orcs and goblins exist in various fictional settings, generally the concept of orcs is derived from either the Tolkien or Gygax version. It is generally accepted they have green skin, covered in thick dark hair and warts, and are large and bulky in physical stature with a some what feral look.
Blah blah blah....I hope this helps.
-----------------
[1] Douglas A. Anderson: The Annotated Hobbit
[2] Nomenclature of The Lord of the Rings