Origin and history of excursion

[move quickly in search of something], c. 1300, scouren, a word of uncertain origin, probably from Old Norse skyra "rush in," related to skur "storm, shower, shower of missiles" (see shower (n.)). This was likely influenced by or blended with Old French escorre "to run out," from Latin excurrere (see excursion).

The sense also probably has been influenced by scour (v.1) "cleanse by hard rubbing" and entangled with it in some figurative uses and in phrases such as scour the countryside "clear (a place) of enemies or undesirable persons." Middle English also had it as a noun, as in the expression in good scour "quickly, with all haste" (c. 1300).

word-forming element, in English meaning usually "out of, from," but also "upwards, completely, deprive of, without," and "former;" from Latin ex "out of, out from the interior of a thing" (in opposition to in), "from within; from which time, since; according to; in regard to." This is reconstructed to be 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.

Often reduced to e- before -b-, -d-, -g-, consonantal -i-, -l-, -m-, -n-, -v- (as in elude, emerge, evaporate, etc.).

The sense in Latin naturally tended toward "thoroughly, utterly," and in some English ex- words with no clear connection to the idea of "out of," the element might be purely intensive. Among them are exhort, exhilarate, evident, excruciate, exclaim, exuberant, exaggerate, expiate, expect.

For use of Latin ex- as "(rise) up out of," as preserved in English emerge, emend, the notion is "out from the interior of a thing," in opposition to in-. Hence also in Latin, "in an upward direction," as in effervesce, exult, extol.

PIE *eghs had comparative form *eks-tero and superlative *eks-t(e)r-emo-.

Proto-Indo-European root meaning "to run."

It might form all or part of: car; career; cargo; caricature; cark; carpenter; carriage; carrier; carry; charabanc; charette; charge; chariot; concourse; concur; concurrent; corral; corridor; corsair; courant; courier; course; currency; current; curriculum; cursive; cursor; cursory; discharge; discourse; encharge; excursion; hussar; incur; intercourse; kraal; miscarry; occur; precursor; recourse; recur; succor.

It might also be the source of: Greek -khouros "running;" Latin currere "to run, move quickly;" Lithuanian karšiu, karšti "go quickly;"Old Irish and Middle Welsh carr "cart, wagon," Breton karr "chariot," Welsh carrog "torrent;" Old Norse horskr "swift."