Goblin is another name for an Orc - especially the smaller kinds that infested the Misty Mountains and the Grey Mountains.

Goblin-men are mentioned once in "Lord of the Rings". These were creatures created by Saruman, apparently by blending the races of Orcs and Men. Exactly what these goblin-men were is unknown - they are only ever mentioned once by name, during the Battle of the Hornburg.
Encyclopedia entry originally written by hungry123hobbit