[ hā-dē′ən ]
The period of geologic time between 4.6 and 3.8 billion years ago, when the solar system was forming and the Earth was solidifying. No rocks are known from this time, as they were presumably eroded or drawn deep into the Earth and melted through the processes of plate tectonics. See Chart at geologic time.
Super Spooky Night Time WordsWhether you like nightfall or not, these literary words help capture its truest form, ranging from spooky to serene, and everything in between.
Is It “Sometime,” “Sometimes,” Or “Some Time”?While they appear very similar, sometime, sometimes, and some time have slightly different meanings. Sometime means a vague point in time, and usually refers to a long amount of time. Sometimes means occasionally. Some time refers to a period of time. Sometime Sometime refers to an unspecified point in time. It functions as an adverb, and is also synonymous with someday, one day, or sooner …
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.