Elf-knight

Hurrah! hurrah! the elf-knights enter. Each with his grasshopper at a canter!

Source: wiktionary

She heard an Elf knight his horn blowing, The first morning in May.

Source: wiktionary

And the sword that had visited Earth from so far away smote like the falling of thunderbolts [...] and the runes in Alveric’s far-travelled sword exulted, and roared at the elf-knight; until in the dark of the wood, amongst branches severed from disenchanted trees, with a blow like that of a thunderbolt riving an oak-tree, Alveric slew him.

Source: wiktionary