'post-split' is formed from Latin-derived 'post' and English 'split'. 'post' originates from Latin 'post', where 'post' meant 'after'. 'split' originates from Old English/Proto-Germanic roots (e.g., Old English 'splītan' / Proto-Germanic '*splitaną'), meaning 'to divide' or 'to cleave'.

'post' entered English via Late Latin and Old French usage as a preposition/adverb meaning 'after'; 'split' developed in Old English and Middle English from Germanic roots (Old English 'splītan' and related forms) into the modern verb and past-participle 'split'. The compound 'post-split' is a modern English formation combining the temporal prefix 'post-' with the past-participle 'split' to describe the period or state after a division.

Initially, 'post' simply meant 'after' and 'split' meant 'to divide/cleave'; combined into 'post-split' the phrase came to specify the time, condition, or attributes occurring after a formal split (especially in business/financial contexts).