An adjective glossed “difficult, laborious” in Definitive Linguistic Notes (DLN) from 1959 derived from the root √GUR of similar meaning (PE17/154). Tolkien indicated it was used mainly “in a very strong sense of things very painful and horrible to do”; see the entry on its prefixal form gor- for discussion. A more ordinary adjective for “hard, difficult” was dîr.
Sindarin
gordh
difficult
gordh
adjective. difficult, laborious
gordh
noun. deep thought
{ð}_ adj. _difficult, laborious. Q. urda hard, difficult, arduous. >> gornod