accretionary hypothesis

noun

: any explanation of the origin of the earth that involves the hypothesis of gradual growth by the gravitational infall of solid bodies (as asteroids, planetesimals, or meteorites) compare planetesimal hypothesis

Word History

First Known Use

1905, in the meaning defined above

The Ultimate Dictionary Awaits

Expand your vocabulary and dive deeper into language with Merriam-Webster Unabridged.

1. Expanded definitions
2. Detailed etymologies
3. Advanced search tools
4. All ad-free

Discover what makes Merriam-Webster Unabridged the essential choice for true word lovers.

Start Your Free Trial Now