Silliness is behaviour that shows no sense, usually harmlessly. A moment of silliness.
It is affectionate where foolishness is not, which is the whole difference. The word silly once meant blessed and then innocent before it meant anything like this.
1nounsillinessBehaviour that shows no sense, usually harmlessly.
“The silliness on the last day of term was expected by everybody.”
silliness is a behaviour.
Proto-West Germanic
*sālīg
Old English
sǣliġ
Middle English
seely
English
silly
English, today
silliness
Built from
From silly + -ness. silly comes from Middle English seely, seli, from Old English sǣliġ, ġesǣliġ (“lucky, fortunate”), from Proto-West Germanic sālīg, from sāli; equivalent to seel + -y. a doublet of Seelie. The semantic evolution is “lucky” to “innocent” to “naive” to “foolish”. Compare the similar evolution of daft (originally meaning “accommodating”), and almost the reverse with nice (originally meaning “ignorant”).
Etymology from Wiktionary, CC BY-SA