'unisporangiate' originates from Neo-Latin, specifically the compound 'unisporangium' (formed from Latin prefix 'uni-' and Greek 'sporangion'), where 'uni-' meant 'one' and Greek 'sporangion' (from 'spora' + 'angeion') meant 'spore-vessel'.

'unisporangiate' developed by combining the Neo-Latin formation 'unisporangium' with the English adjectival suffix '-ate'; 'sporangion' came from Greek 'spora' (seed/spore) + 'angeion' (vessel), passed into Neo-Latin as 'sporangium', and then into English scientific usage as part of compounds like 'unisporangiate'.

Initially, it meant 'having a single sporangium' in technical botanical usage, and this basic meaning has been retained in modern usage.