'astrodome' was coined in English in the mid-20th century by combining the prefix 'astro-' (relating to stars) with the noun 'dome' (a rounded roof or vault). The name was popularized as the proper name 'Astrodome' for the Houston stadium.

The element 'astro-' comes from Greek 'astron' meaning 'star'. 'Dome' derives from Latin/Greek roots (Latin 'domus' house via Greek 'domos' or Late Latin 'doma' for roof), evolving into English 'dome'. The coined form 'Astrodome' (proper noun) entered English usage in the 1960s and later became a generic term for similar domed stadiums.

Initially, it referred specifically to the trademarked Houston 'Astrodome' (a single building). Over time the word broadened to mean any large domed stadium or arena.