'carbohydrate-accumulating' is a modern English compound built from 'carbohydrate' and 'accumulate'. 'carbohydrate' originates (via Modern French/New Latin) from the New Latin word 'carbohydratum', where 'carbo-' meant 'coal/carbon' and Greek 'hydor' (rendered as 'hydrate') meant 'water'; 'accumulate' originates from Latin, specifically the word 'accumulare', where the prefix 'ad-' meant 'to' and 'cumulare' meant 'to heap'.

'carbohydrate' entered scientific English in the early 19th century from New Latin/French 'carbohydratum'; 'accumulare' passed from Latin into Old French and Middle English as forms of 'accumulate'; in modern English these elements were combined into the descriptive compound adjective 'carbohydrate-accumulating'.

Initially, 'carbohydrate' referred specifically to the chemical notion of a 'hydrate of carbon' and 'accumulate' meant 'to heap up'; combined as 'carbohydrate-accumulating' the phrase came to mean 'tending to store or build up carbohydrates', a usage now chiefly found in biological and biochemical descriptions.