excursion (n.) Look up excursion at Dictionary.com
1570s, "a deviation in argument," also "a military sally," from Latin excursionem (nominative excursio) "a running forth, sally, excursion, expedition," noun of action from past participle stem of excurrere "run out, run forth, hasten," from ex- "out" (see ex-) + currere "to run" (see current (adj.)). Sense of "journey" recorded in English by 1660s.