Definitions:

1. large in amount, extent, or degree adjective
   • A hefty 1 million people have helped out.
2. of considerable weight and size adjective
   • The hefty dictionary has at least 1000 pages.
3. possessing physical strength and weight, referring to a person adjective
   • My hefty cousin chopped down trees for a living.

Synonyms:

• brawny
• goodly
• muscular
• powerful
• sinewy