planetesimal.

A solid body in a young planetary system that can collide and combine with others during planet formation.

Use it for

Words that belong together

• icy planetesimal
• planetesimal collision

On the page

Two planetesimals collided beyond the young star’s snow line.

The simulation showed rocky planetesimals gathering into larger worlds.

Usage notes

Primary category: sci-fi. Forms: Singular: planetesimal; plural: planetesimals. Legacy lexical fields mirror sense 1 only. Use numbered sense fields for all meanings.