weighty in WordNet English dictionary

1. powerfully persuasive
   "a cogent argument"; "a telling presentation"; "a weighty argument"
   cogent  telling  weighty 
   
2. excessively fat
   "a weighty man"
   corpulent  obese  weighty  rotund 
   
3. of great gravity or crucial import; requiring serious thought
   "grave responsibilities"; "faced a grave decision in a time of crisis"; "a grievous fault"; "heavy matters of state"; "the weighty matters to be discussed at the peace conference"
   grave  grievous  heavy  weighty 
   
4. having relatively great weight; heavy
   "a weighty load"; "a weighty package"
   weighty 
   
5. weighing heavily on the spirit; causing anxiety or worry
   "weighty problems"
   weighty