h₂eyd-ero-

“upper air, bright sky”

Widely acceptedskyquality

ether, ethereal, serene

Extended adjectival from *h₂eyd- giving Greek aithēr, English ether, ethereal.‍‍‌‍‌‌‌‌‍‍‌‌‌‍‍‌‍‍‌‌‍‌‌‍‌‍‍‍‍‌‍‍

bʰerǵ-eyo-“to keep brightening, shining”deru-“tree, wood, to be firm”dʰeh₁-ḱ-ul-“easy to make, manageable”dʰeh₁-rm-“that which is heated, warm”dʰerǵʰ-mn̥-“firmness, hardness, endurance”gʰeHd-“to unite, join, be fitting”gʷerh₃-tú-“heaviness, weight, dignity”gʷeyh₃-wó-“alive, living, vital”