Definition of planetokhod in US English:

planetokhod

noun

Astronautics
rare
  • A self-propelled vehicle for transmitting information about a planet as it travels over its surface.

Origin

1970s; earliest use found in The Times. From Russian planetoxod (also transliterated planetokhod) from planeta + -o- + -xod (in e.g. pešexod (noun) pedestrian; compare xod motion, movement, travel) from xodit′ to go, walk.