'starch-deficient' originates from Modern English as a compound of 'starch' and 'deficient'. 'starch' ultimately comes from Old English 'stearc', and 'deficient' comes from Latin 'deficere' (via Old French).

'starch' changed from Old English 'stearc' (meaning 'stiff') and came to denote the powdered or thickening substance used in cooking and textiles; 'deficient' entered English from Old French and Latin 'deficiens' / 'deficere' meaning 'to fail or be lacking', and combined in Modern English to form compounds like 'starch-deficient'.

Initially, 'starch' meant 'stiff' (referring to stiffness imparted by the substance) and later shifted to the substance and its nutritional sense; 'deficient' originally meant 'failing' or 'lacking' and retained the sense of 'not having enough', which together yield the current meaning 'lacking starch'.