See Also: planetesimal(dictionary)
planetesimal(encyclopedia)

planetesimal (iou)



planetesimal noun & adjective. 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.