Definitions of weighty:

• adjective:   having relatively great weight; heavy

  Example: "A weighty load"

• adjective:   weighing heavily on the spirit; causing anxiety or worry

  Example: "Weighty problems"

• adjective:   powerfully persuasive

  Example: "A weighty argument"

• adjective:   excessively fat

  Example: "A weighty man"

• adjective:   of great gravity or crucial import; requiring serious thought

  Example: "The weighty matters to be discussed at the peace conference"