astronomical frame of reference
a frame of reference in which the sun or center of mass of the universe is fixed and which does not rotate with respect to the fixed stars.
Five English Words That Are Utterly UniqueRead more in this article about some frequently asked questions and fun facts related to our definitions.
When Does Summer Really End?Summer is the season for basking in the warm sun and rejoicing in the freedom of summer vacation. So when the rest and relaxation is shooed away for cooler days and the start of school, it’s easy to forget that the summer season is far from over. Many consider Labor Day the final hurrah of summer, but we still have a few weeks after that …
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019