'appetitious' originates from Latin, specifically the word 'appetitiosus' (from 'appetitus'), where 'appetitus' meant 'a longing, desire', ultimately from 'appetere' meaning 'to seek or desire' (from ad- + petere).

'appetitious' changed from Late Latin/Medieval Latin 'appetitiosus' (and related forms such as 'appetitus') and was adopted into English usage in later periods as the adjective 'appetitious'.

Initially it meant 'having desire' in a general sense, and over time it retained this core idea but also came to be used specifically as 'relating to appetite' or 'arousing appetite'.