An Etymological Dictionary of the German Language/Annotated/Spanferkel
Spanferkel, neuter, ‘sucking pig,’ a diminutive of Middle High German spęnvarch, neuter, ‘sucking pig’ (also in Middle High German spęn-sû-, -swîn). The first component is Middle High German spęn, feminine, ‘breast, milk,’ on whose equivalent variant spüne, spünne, Middle High German spünnevęrchelîn, ‘sucking pig,’ is based. Compare Dutch speen, ‘udder,’ and Old High German spunni, feminine, ‘breast,’ whose root is perhaps the same as that of spannen; akin also to Lithuanian spenýs, ‘teat.’