Explore
mid 16th century (in the sense ‘investigate (why)’): from French explorer, from Latin explorare ‘search out’, from ex- ‘out’ + plorare ‘utter a cry’.
wiktionary
From Middle French explorer, from Latin explōrāre(“to investigate, search out”), itself said to be originally a hunters' term meaning "to set up a loud cry", from ex-(“out”) + plōrāre(“to cry”), but the second element is also explained as "to make to flow" (from pluere(“to flow”)).
etymonline
explore (v.)
1580s, "to investigate, examine," a back-formation from exploration, or else from French explorer (16c.), from Latin explorare "investigate, search out, examine, explore," said to be originally a hunters' term meaning "set up a loud cry," from ex "out" (see ex-) + plorare "to weep, cry." Compare deplore. De Vaan notes modern sources that consider "the ancient explanation, ... that the verb explorare originally meant 'to scout the hunting area for game by means of shouting'" to be "not unlikely." Second element also is explained as "to make to flow," from pluere "to flow." Meaning "to go to a country or place in quest of discoveries" is first attested 1610s. Related: Explored; exploring.
