'non-septate' originates from a combination of the prefix 'non-' (from Latin 'non', meaning 'not') and 'septate', which ultimately comes from Latin 'septum' meaning 'fence, enclosure, partition'.

'septate' derives from Late Latin/Medieval Latin formations related to 'septum' (Latin), with the adjectival English form 'septate' formed by the addition of the suffix '-ate'; 'non-' was then prefixed in English to indicate the negative, yielding 'non-septate'.

Initially, the root 'septum' meant 'a fence or partition'; 'septate' came to mean 'having septa/partitions', and 'non-septate' developed to mean 'not having septa' or 'without partitions' in modern scientific usage.