sinewy vs hefty

sinewy and hefty both are adjectives.

Word	Noun	Adjective	Verb	Adverb
sinewy	No	Yes	No	No
hefty	No	Yes	No	No

As adjectives, sinewy and hefty are synonyms defined as:

sinewy and hefty: (of a person) possessing physical strength and weight; rugged and powerful

Other synonyms of sinewy include brawny, muscular, powerful.

sinewy (adjective)	hefty (adjective)
consisting of tendons or resembling a tendon	large in amount or extent or degree
(of a person) possessing physical strength and weight; rugged and powerful	of considerable weight and size
(of meat) full of sinews; especially impossible to chew	(of a person) possessing physical strength and weight; rugged and powerful