Weighty (adjective)

1. Having great weight.
2. Having importance or significance.
3. Having moral or intellectual gravity.
4. Having a substantial or heavy feel.

Origin:

Middle english weghty, from weght weight.

Examples:

1. This is a weighty matter that requires careful consideration.
2. The weighty book was difficult to carry around.
3. He made a weighty decision that would affect the company for years to come.
4. The weighty gold necklace was passed down through generations.
5. The topic was weighty, but the conversation was lively and engaging.