astro-

American  

1. a combining form with the meaning “pertaining to stars or celestial bodies, or to activities, as spaceflight, taking place outside the earth's atmosphere,” used in the formation of compound words.

   astronautics; astrophotography.

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astro- British  

combining form

1. indicating a heavenly body, star, or star-shaped structure

   astrology

   astrocyte

2. indicating outer space

   astronautics

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astro– Scientific  

1. A prefix that means “star” (as in astrophysics), “celestial body” (as in astronomy), or “outer space” (as in astronaut).

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Usage

What does astro- mean? Astro- is a combining form used like a prefix meaning “related to stars, celestial bodies, and outer space.” It is often used in scientific terms, especially in—you guessed it—astronomy.Astro- is also sometimes used to refer to something that is star-shaped, as in an astrocyte, a type of star-shaped cell in the brain and spinal cord.Astro- comes from the Greek ástron, meaning “star.” The Greek ástron is also related to such words as asteroid and even the star itself. The word astronomy comes from a Greek word that literally (and poetically) means “star-arranging.”What are variants of astro-?When combined with words or word elements that begin with a vowel, astro- becomes astr-.

Etymology

Origin of astro-

< Greek, combining form of ástron a star, constellation, akin to astḗr star; aster, -aster ²

Example Sentences

Organisers say there were 154 million livestreams in 2024, when platformer Astro Bot was named Game of the Year.

From BBC

The gritty, sci-fi murder mystery series is based on a reimagining of a story arc from the “Astro Boy” manga, and is set in a world where humans live alongside robots — though the dynamic is a bit different than in “Star Wars.”

From Los Angeles Times

Nicole Carr and Simon Scott, from Astro Dog, a firm which runs stargazing, photography and education events, said people who were able to travel could use weather radar apps to find gaps in the cloud.

From BBC

The beloved People Mover would be no more, a Jules Verne-inspired art style would come and gradually go, and Buzz Lightyear Astro Blasters would arrive in 2005.

From Los Angeles Times

Brain cancer is - according to the Astro Brain Fund charity - the most fatal of all in terms of years lost, but investigations into it represent just 1% of the national spend on cancer research since records began.

From BBC