There were bones on the floor and a nasty smell was in the air; but there was a good deal of food jumbled carelessly on shelves and on the ground, among an untidy litter of plunder, of all sorts from brass buttons to pots full of gold coins standing in a corner. There were lots of clothes, too, hanging on the walls-too small for trolls, I am afraid they belonged to victims-and among them were several swords of various makes, shapes, and sizes. Two caught their eyes particularly, because of their beautiful scabbards and jewelled hilts. Gandalf and Thorin each took one of these; and Bilbo took a knife in a leather sheath. It would have made only a tiny pocket-knife for a troll, but it was as good as a short sword for the hobbit.
"These look like good blades," said the wizard, half drawing them and looking at them curiously. "They were not made by any troll, nor by any smith among men in these parts and days; but when we can read the runes on them, we shall know more about them."

(The Hobbit, Ch. 2, Roast Mutton)

Elrond knew all about runes of every kind. That day he looked at the swords they had brought from the trolls' lair, and he said: "These are not troll-make. They are old swords, very old swords of the High Elves of the West, my kin. They were made in Gondolin for the Goblin-wars. They must have come from a dragon's hoard or goblin plunder, for dragons and goblins destroyed that city many ages ago. This, Thorin, the runes name Orcrist, the Goblin-cleaver in the ancient tongue of Gondolin; it was a famous blade. This, Gandalf, was Glamdring, Foe-hammer that the king of Gondolin once wore. Keep them well!"
"Whence did the trolls get them, I wonder?" said Thorin looking at his sword with new interest.
"I could not say," said Elrond, "but one may guess that your trolls had plundered other plunderers, or come on the remnants of old robberies in some hold in the mountains of the North. I have heard that there are still forgotten treasures of old to be found in the deserted caverns of the mines of Moria, since the dwarf and goblin war."
Thorin pondered these words. "I will keep this sword in honour," he said."May it soon cleave goblins once again!"
"A wish that is likely to be granted soon enough in the mountains!" said Elrond.

(The Hobbit, Ch. 3, A Short Rest)

He held out the sword which Thorin had worn, the sword which came from the Trolls' lair.
The Great Goblin gave a truly awful howl of rage when he looked at it, and all his soldiers gnashed their teeth, clashed their shields, and stamped. They knew the sword at once. It had killed hundreds of goblins in its time, when the fair elves of Gondolin hunted them in the hills or did battle before their walls. They had called it Orcrist, Goblin-cleaver, but the goblins called it simply Biter. They hated it and hated worse any one that carried it.

(The Hobbit, Ch. 4, Over Hill and Under Hill)

They buried Thorin deep beneath the Mountain, and Bard laid the Arkenstone upon his breast.
"There let it lie till the Mountain falls!" he said. "May it bring good fortune to all his folk that dwell here after!" Upon his tomb the Elvenking then laid Orcrist, the elvish sword that had been taken from Thorin in captivity. It is said in songs that it gleamed ever in the dark if foes approached, and the fortress of the dwarves could not be taken by surprise.

(The Hobbit, Ch. 18, The Return Journey)

ris - 'cleave' appears to have blended with the stem kris- of similar meaning (a derivative of the root kir-'cleave, cut', q.v.); hence Angrist (also Orcrist 'Orc-cleaver', the sword of Thorin Oakenshield), Crissaegrim,Imladris.

(Silm, Appendix)