Any of the four gas giant planets in the Solar System: Jupiter, Uranus, Saturn, or Neptune.

A system of gears that has a central gear wheel (sun gear) around which others (planet gears) rotate, often within an outer ring.

(astronomy) Of, or relating to planets, or the orbital motion of planets. / Of, or relating to the Earth; terrestrial. / Of, or relating to the whole Earth; global. / (of a gear train) epicyclic

A planetary nebula.

comparative form of plane: more plane

A woodworking tool which smooths a surface or makes one surface of a workpiece parallel to the tool's bed.

A display museum in which images of stars and other astronomical phenomena are projected onto a domed ceiling. / An orrery.

plural of planetarium

plural of planetarium

An assembly of meshed gears consisting of a central (sun) gear, a coaxial internal gear-wheel and one or more intermediate pinions supported on a revolving carrier.