'ascendable' originates from Latin, specifically the word 'ascendere', where 'ad-' (present as 'as-' before 'c') meant 'to' and 'scandere' meant 'to climb'; the adjectival suffix '-able' comes from Latin '-abilis' via Old French '-able', meaning 'able to be'.

'ascendable' developed by combining the verb 'ascend' (from Latin 'ascendere' through Old French/Medieval Latin and Middle English 'ascenden/ascend') with the Old French/Latin-derived suffix '-able', resulting in the modern adjective 'ascendable'.

Initially the root 'ascendere' meant 'to climb', and over time the formed adjective came to mean 'capable of being climbed or ascended' (a passive or potential sense).