excess (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.).

Proto-Indo-European root meaning "to go, yield."

It forms all or part of: abscess; accede; access; ancestor; antecede; antecedent; cease; cede; cession; concede; decease; exceed; excess; incessant; intercede; necessary; precede; predecessor; proceed; recede; recess; recession; secede; secession; succeed; success.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit sedhati "to drive, chase away;" Avestan apa-had- "turn aside, step aside;" Latin cedere "to yield, give place; to give up some right or property," originally "to go from, proceed, leave;" Old Church Slavonic chodu "a walking, going," choditi "to go."