* Nautical: Relating to sailors, ships, or navigation.
* Astronaut: A person who travels in space.
* Cosmonaut: A Russian or Soviet astronaut.
* Taikonaut: A Chinese astronaut.
* Aquanaut: A person who lives and works underwater.
* Argonaut: In Greek mythology, a sailor on the ship Argo.
These words all share the common element of referring to someone who travels or explores in some way.