'astroalchemist' is a modern English compound formed from the combining form 'astro-' (from Greek 'astron', meaning 'star') and the noun 'alchemist' (from 'alchemy'), where 'astro-' meant 'star' and 'alchemist' referred to a practitioner of alchemy.

'alchemist' changed from Medieval Latin word 'alchimista' and Old French 'alquimiste' and eventually became the modern English word 'alchemist'; the combining element 'astro-' comes from Greek 'astron'. The compound 'astroalchemist' is a recent creative formation in English rather than a historically attested single-word lineage.

Initially, 'alchemist' referred specifically to practitioners attempting material transmutation and the search for the philosopher's stone; over time its meaning broadened to include metaphorical transformation. 'Astroalchemist' began as a creative/fictional coinage meaning someone who seeks to transform or harness stars, and it is used mainly metaphorically or in speculative contexts.