'multi-flowered' originates from the Latin prefix 'multi-' (from Latin 'multus') meaning 'many' combined with English 'flower' (from Old English 'flōwer' via Old French 'flor' and Latin 'flōs, flōris').

'flower' changed from Latin 'flōs, flōris' to Old French 'flor' and Old English 'flōwer', eventually becoming the modern English word 'flower'; the productive Latin prefix 'multi-' was later attached in English to form compounds such as 'multi-flowered'.

Initially, the elements meant 'many' + 'flower'; over time the compound retained this literal sense and came to be used especially in botanical description to mean 'having many flowers'.