The story
- Middle English · borrowed fromdwarrows
- English todaydwarrow
Coined by J. R. R. Tolkien as a back-formation of Middle English dwarrows, an irregular plural of dwergh, which became dwarfs in Modern English through leveling with dwarf. Within Tolkien's legendarium, dwarrow is only used in Dwarrowdelf, an alternative name for Moria (see the quotations by Tolkien).
Etymology from Wiktionary, CC BY-SA 4.0.