Stage of in this word's full journey.
Where does the word "silly" come from? It comes from Old English gesǣlig, passing through Middle English before entering English (1570s).
Silly’s story begins in Old English: gesǣlig meant “blessed, happy.” 'happy, blessed, fortunate', from sǣl 'happiness'; German selig still means 'blessed'. By 1300s, the word had taken hold in Middle English as seely. Slid from 'blessed' to 'innocent, harmless', then 'pitiable, helpless', as in the 'seely' sheep of medieval verse. It reached English by 1570s as silly. Sank to 'foolish'; journalists' 'silly season' for the trivial summer news of August and September dates from an 1861 article in The Saturday Review. Today, silly means lacking good sense; foolish.