'sausage-fingered' originates from Modern English, a compound formed from 'sausage' + past participle 'fingered' to describe fingers resembling sausages.

'sausage' comes from Old French 'saussiche' (or 'saucisse'), from Vulgar Latin 'salsica' (from Latin 'salsus' meaning 'salted'); 'fingered' derives from Old English 'finger' (from Proto-Germanic '*fingraz'). The compound 'sausage-fingered' arose in colloquial English by analogy to other vivid, descriptive compounds.

Initially a literal image (fingers like sausages); over time used figuratively to describe clumsiness or lack of fine manual dexterity.