Standard Lemma guide

planetesimal

adj · noun · 3 senses · updated from the 2026-07-25 local source snapshot

Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.

Sound

Pronunciation

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No pronunciation record was provided for this word.

1

adj

Meaning 1

Being or relating to one of these astronomical objects.

Definition source: English Wiktionary via Wiktextract

Usage: not-comparable

Topics: astronomy, natural-sciences

Examples

  • a planetesimal body

Meaning relationships

Synonyms: none provided

Antonyms: none provided

2

noun

Meaning 2

Any of many small, solid astronomical objects that orbit a star and form protoplanets through mutual gravitational attraction.

Definition source: English Wiktionary via Wiktextract

Topics: astronomy, natural-sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

3

noun

Meaning 3

one of many small solid celestial bodies thought to have existed at an early stage in the development of the solar system

Definition source: Princeton WordNet 3.0

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

Broader terms: celestial body, heavenly body

History

Etymology

Formed from planet by analogy with infinitesimal.

Across languages

Translations

6 source translations are retained for this English entry.

  • Finnish: planetesimaali — a small, solid astronomical object
  • Georgian: პლანეტოშენადედი (ṗlaneṭošenadedi) — a small, solid astronomical object
  • German: Planetesimal — a small, solid astronomical object
  • Polish: planetozymal — a small, solid astronomical object
  • Portuguese: planetesimal — a small, solid astronomical object
  • Russian: планетезима́ль (planetɛzimálʹ) — a small, solid astronomical object