(crystallography) A plane of molecular weakness that allows movement without fracture.

(astronomy) A theoretical type of terrestrial planet that could form, if protoplanetary discs are carbon-rich and oxygen-poor.

A carbon planet.

epiphyte

(botany) A plant which reproduces by breading seeds in the wide sense of the term, including spores etc.

A general-purpose bench plane, used for general sizing of wood and for smoothing or straightening edges.

(engineering) A plane which serves as a reference or base for the measurement of other quantities.

The state of being plangent.

plural of planetary nebula

plural of planetary nebula