As a noun protoplanet
is an astronomical object, approximately the size of the Moon, formed from the mutual gravitational attraction of planetesimals; they are thought to collide with each other and slowly form planets.
As an adjective nebular is
of or pertaining to a nebula.
protoplanet
English
Noun
(
wikipedia protoplanet)
(
en noun)
An astronomical object, approximately the size of the Moon, formed from the mutual gravitational attraction of planetesimals; they are thought to collide with each other and slowly form planets
Derived terms
* protoplanetary
nebular
English
Adjective
(-)
(astronomy) Of or pertaining to a nebula
Related terms
* nebulosity
* nebulous
* nebula