any elastic wave traveling through the material of the earth, as a wave caused by an earthquake.
When To Capitalize “Earth”When it comes to writing, this common English word confuses many native speakers who aren’t sure whether to use Earth or earth. Why is this an issue? Earth can be either a proper noun or a common noun. In English, proper nouns (nouns which signify a particular person, place, or thing) are capitalized. Following this rule, when Earth is discussed as a specific planet or …
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019