Definition of Alpha Centauri
: a binary star of magnitude zero that is the brightest star in the southern constellation Centaurus The plot centered on scientists John and Maureen Robinson and their three children, who in 1997 leave an overpopulated Earth to colonize a planet near Alpha Centauri. — Diane Tedeschi, Air & Space Smithsonian, August/September 1988 ◆What is visible in the night sky as the star Alpha Centauri is actually a binary system: two stars bound together gravitationally.
Love words? You must — there are over 200,000 words in our free online dictionary, but you are looking for one that’s only in the Merriam-Webster Unabridged Dictionary.
Join MWU now and get access to America’s largest dictionary, with:
- 300,000 words that aren't in our free dictionary
- Expanded definitions, etymologies, and usage notes
- Advanced search features
- Ad free!
Origin and Etymology of alpha centauri
borrowed from New Latin, “Alpha of Centaurus”
First Known Use: 1777
Seen and Heard
What made you want to look up Alpha Centauri? Please tell us where you read or heard it (including the quote, if possible).