Meaning of “silly” - Learner’s Dictionary

silly

adjective uk us /ˈsɪli/
STUPID

B1 stupid:

silly games/hats
I feel silly in this hat.
It's a bit silly spending all that money on something we don't need.
UNIMPORTANT

B1 small and not important:

She gets upset over such silly things.
silliness noun [ U ]

(Definition of “silly” from the Cambridge Learner’s Dictionary © Cambridge University Press)