Any of a set of parameters for a quasi-experimental model used to describe the directional reflectance properties of the airless regolith surfaces of bodies in the Solar System.

A text placed alongside its translation or translations. / A text similar to one being translated.

(topology) The non-intuitive fact that it is possible to turn a sphere inside out in a three-dimensional space with possible self-intersections but without creating any crease.

An island in the Bahamas.

Inability to walk due to paralysis of leg muscles.

A colourful, medium-sized parrot, Psephotus pulcherrimus, native to the grassy woodlands of the Queensland - New South Wales border area of northeastern Australia, believed to be extinct.

plural of parasitic element

(electronics) A circuit element or property that is present within an electrical component, and has a negative effect on the performance of the circuit.

plural of parallel world

(science fiction, sciences) A reality or world that exists simultaneously with ours, but independent of it.