planetesimal noun & adjective.
[planɪ'tɛsɪm(ǝ)l] E20.[from PLANET noun1 + INFINIT)ESIMAL adjective.]Astronomy.
A. noun. A small solid body following a planetary orbit; a miniature planet.
E20.b. adjective. Pertaining to, involving, or composed of planetesimals;
esp. designating the hypothesis that the planets were formed by the accretion of a vast number of planetesimals in a cold state.
E20. [TahlilGaran] English Dictionary ▲