Got this from some site. Don't know if it acknowledges / clarifies the fact that Tolkien created the orcs. But a very interesting piece of information nonetheless. 😄
ORCS Also called: Orks, Goblins; Sindarin: Yrch (sg. Orch), Quenya (Valinorean): Urqui (sg. Urko), Quenya (Noldorin): Orqui or Orkor (sg. Orko), Adunaic: (sg.) Urku or Urkhu, Black Speech: Uruk (for lesser breeds: Snaga), Druedainic: Gorgun, Khuzdul: Rakhas (sg. Rukhs);
All (or most of) these names stemming from Proto-Eldarin root *RUKU, "something that causes fear". Sindarin also Glamhoth: "host of tumult" {1}.
A race of evil beings, bred by Melkor in mockery of the Elves of Ilúvatar. The first Orcs were probably bred out of Elves, although some may have been lesser corrupted Maiar. Later on the Orcs were undoubtably bred both out of Elves, Men, and Maiar {2}.