noun. Red is an adjective to describe this ball. Red is an adjective to describe this ball. The definition of an adjective is a part of speech that is used to describe a noun. Red, tall, better and fast are all examples of adjectives.
Geo is defined as related to the Earth. An example of geo is geophone which is a device that detects seismic activity beneath the earth's surface. 1  earth, of the earth: geocentric, geophyte.  geographical: geopolitics.
See more synonyms on Thesaurus.com. noun, plural geometries. 1. the branch of mathematics that deals with the deduction of the properties, measurement, and relationships of points, lines, angles, and figures in space from their defining conditions by means of certain assumed properties of space.