One who goes where they have not been in order to find out. An explorer accepts not knowing what they will meet.
Latin explorare (to search out, to scout); traditionally parsed as ex- plus plorare (to cry out), the cry a scout was said to raise on sighting what was sought, though that reading is the old grammarians' guess rather than a secured derivation.
The old grammarians read its second half as a cry, the shout a scout was said to raise on sighting what was sought, though that reading is tradition more than certainty. Even its own word is comfortable not knowing for sure, a fitting inheritance for one who goes looking without a guarantee of what they will meet.