Plural of daffadilly; an archaic or poetic spelling variant of daffodils, the yellow spring flowers.
From earlier daffodilly, a variant of daffodil (from Arabic al-narcis). The folk-etymology addition of daff- made people think it related to 'daft' (silly).
Daffadilly is such a fun sound that Shakespeare used it, but nobody's sure if it's actually related to daff (foolish)—the flower name might just sound goofy by accident!
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