Silly

1. 1. exhibiting or indicative of a lack of common sense or sound judgment
      // a very silly mistake
   2. weak in intellect
      // acting like a silly fool
   3. playfully lighthearted and amusing
      // a silly sense of humor
   4. TRIFLING, FRIVOLOUS
      // a silly waste of time
   5. being stunned or dazed
      // scared silly
      // knocked me silly
2. aarchaic : RUSTIC, PLAIN
   // The silly buckets on the deck,/That had so long remained,/I dreamt that they were filled with dew;/And when I awoke, it rained.
   — Samuel Taylor Coleridge
3. obsolete : lowly in station : HUMBLE
4. archaic : HELPLESS, WEAK

Thanks to Merriam-Webster