interplanetary
/ɪntɚˈplænɪˌtɛəri/ adjective C2- Existing or occurring between planets. · Humans are just beginning to explore interplanetary travel.
Learn interplanetary in real texts
With a free account, hover any word in the library for its meaning, hear it read aloud, save words for review timed to your memory, and see how much of each book you already know.