'scythe-shaped' originates as a compound of two Old English elements: 'siðe' (Old English for 'scythe') and 'shape' (from Old English 'sceapian'/'scēap'), where 'siðe' referred to a long cutting tool and 'shape' referred to form or appearance.

'scythe' changed from Old English 'siðe' to Middle English forms such as 'sithe'/'sithe' and later 'scythe' in modern English; 'shape' changed from Old English 'sceapian'/'scēap' through Middle English 'shapen' to modern 'shape'; the compound 'scythe-shaped' was formed in modern English by combining these elements to describe form.

Initially, 'scythe' meant 'a tool for mowing or cutting' and 'shape' meant 'form'; over time their compound came to be used adjectivally to mean 'having the form of a scythe'.