silly (adjective) silly: absurd, giddy, foolish
Sinonime: asinine,
balmy, brainless,
childish,
crazy, dippy,
dizzy*,
empty, empty-headed,
fatuous, featherbrained, flighty, foolhardy,
frivolous, harebrained,
idiotic,
ignorant,
illogical,
immature,
imprudent,
inane,
inappropriate,
inconsistent,
irrational,
irresponsible,
ludicrous,
meaningless, muddle-headed, nitwitted,
nonsensical,
pointless,
preposterous,
puerile,
ridiculous,
senseless, sheepheaded,
simple, simpleminded,
stupid,
unintelligent,
unreasonable, unwise,
vacuous, witless
Antonime: mature,
mundane,
practical,
sensible,
serious,
wise