hwindë noun (2) "eddy, whirlpool" (SWIN). In the pre-classical Tengwar system presupposed in the Etymologies, hwindë was also the name of tengwa #34, which letter Tolkien would later call hwesta sindarinwa instead.
Quenya
hwindë
birch
hwindë
eddy, whirlpool
hwindë
noun. birch
hwindë (1) noun "birch" (PE17:23)