Definition

A person trained to travel and work in space, specifically in the Russian or Soviet space program.

Example

The cosmonaut floated gracefully in the weightlessness of space.

Conversation

Did you hear about the new documentary on cosmonauts?

Yeah! I’ve always found their missions fascinating.

I learned that the first cosmonaut was Yuri Gagarin.

Exactly! It’s amazing how far space exploration has come since then.

Synonyms & Antonyms

Root Explanation

Cosmonaut is formed from "cosmo-" (from Greek "kosmos", meaning universe or world) and "naut" (from Greek "nautes", meaning sailor). The word describes a sailor of the universe, or someone who travels in space.

Memory Tip

Think of a 'sailor' ('naut') exploring the 'universe' ('cosmo-') — that's why a cosmonaut is someone who travels through space.

Visually Confused Words