'feast-and-famine' is formed from the nouns 'feast' and 'famine'. 'Feast' originates from Old French 'feste' (from Latin 'festus') meaning 'festive, of a feast', and 'famine' originates from Latin 'fames' meaning 'hunger'.

'feast' came into Middle English via Old French as 'fest'/'feste' and developed into modern English 'feast'; 'famine' entered English via Old French 'famine' from Latin 'fames'. The juxtaposition of the two words as a figurative phrase (feast-and-famine) developed in modern English usage to describe alternating abundance and scarcity.

Originally the words described literal conditions (a time of feasting vs. a time of hunger). Over time the combined phrase took on a broader figurative meaning referring to irregular cycles of plenty and shortage in contexts such as work, income, or business.