emotion n.

word-forming element, in English meaning usually "out of, from," but also "upwards, completely, deprive of, without," and "former;" from Latin ex "out of, from within; from which time, since; according to; in regard to," from PIE *eghs "out" (source also of Gaulish ex-, Old Irish ess-, Old Church Slavonic izu, Russian iz). In some cases also from Greek cognate ex, ek. PIE *eghs had comparative form *eks-tero and superlative *eks-t(e)r-emo-. Often reduced to e- before -b-, -d-, -g-, consonantal -i-, -l-, -m-, -n-, -v- (as in elude, emerge, evaporate, etc.).

*meuə-, Proto-Indo-European root meaning "to push away."

It forms all or part of: commotion; emotion; mob; mobile; moment; momentary; momentous; momentum; motif; motility; motion; motive; moto-; motor; move; movement; mutiny; premotion; promote; remote; remove.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit kama-muta "moved by love" and probably mivati "pushes, moves;" Greek ameusasthai "to surpass," amyno "push away;" Latin movere "move, set in motion;" Lithuanian mauti "push on."