at·mos·pher·ics (ăt′mə-sfîrĭks, -sfĕr-)
1. (used with a sing. verb)
a. Electromagnetic radiation produced by natural phenomena such as lightning.
b. Radio interference produced by such radiation. Also called sferics.
2. (used with a pl. verb)
a. Features, events, or statements intended to create a particular mood or attitude: “[This book] is full of fiction unconcerned with spooky atmospherics or suspense; most of the collection's stories are about cruel humans and the violence they commit” (Ken Tucker).
b. The mood or attitude so created.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.