Heliocentrism Definition

noun

The theory that the sun is the center of the universe, (This theory is historically important and was widely accepted at the time of Copernicus, Galileo and Kepler.)

Wiktionary

(astronomy) The theory of the heliocentric model, that the planets including Earth orbit the Sun, in contrast to geocentrism. (This theory, that the sun is the centre of the Solar System only is the current theory.)

Wiktionary

Origin of Heliocentrism

Shortened from heliocentricism < heliocentric + -ism < from Greek ηλιοκεντρικός (heliokentrikos) "having the sun as his centre", from ancient Greek ήλιος (helios) "sun" + κέντρον (kentron) "centre".

From Wiktionary