'ascensive' originates from Latin, specifically the word 'ascensus' (from 'ascendere'), where 'ad-/as-' meant 'to/toward' and 'scandere' meant 'to climb'.

'ascensive' changed from Medieval/Neo-Latin forms such as 'ascensivus' and was formed in English by applying the adjectival suffix '-ive' to the Latin stem 'ascens-', eventually becoming the modern English 'ascensive'.

Initially it meant 'pertaining to ascent' or 'having risen', but over time it evolved into its current sense of 'tending to rise' or 'upward in direction'.