explorer: Meaning and Definition of

ex•plor•er

1. a person or thing that explores.
2. a person who investigates unknown regions: the great explorers of the Renaissance.
3. any instrument used in exploring or sounding a wound, a cavity in a tooth, or the like.
4. (cap.) Also calleda person between the ages 14 and 20 who is an active participant in the exploring program sponsored by the Boy Scouts of America.
5. (cap.)one of a long series of U.S. scientific satellites:(1958) was the first U.S. artificial satellite. Explorer 1