weighty

/ˈweɪti/
adjective
  1. Heavy; having a lot of weight.
    • She carried a weighty backpack full of books.
    • The weighty stone door slowly creaked open.
    • The box was so weighty that I needed help to lift it.
  2. Important, serious, or having a lot of influence.
    • The president made a weighty decision about the country's future.
    • This is a weighty matter that requires careful thought.
    • Her opinion carries weighty authority in the scientific community.
Antonyms
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