Longman Dictionary English

From Longman Dictionary of Contemporary English
Related topics: Astronomy
astro-astro- /æstrəʊ, -trə $ -troʊ, -trə/ prefix XXrelating to the stars, the planets, or space an astronaut (=someone who travels in space) astronomy (=scientific study of the stars)Origin astro- Old French Latin, from Greek, from astron “star”
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