Definition of "grass-fed"

grass-fed

adjective
not comparable
1. Of cattle or other livestock, fed on pasture.
2. Of meat, milk, or other livestock products, derived from livestock fed on pasture.
  Quotations
  The quality of the beef usually met with in the Straits Settlements is so bad and so destitute of flavour, that possibly the buyers had forgotten what an honest sirloin of beef looked like, and the rich edging of fat from grass-fed beef may have struck them as something extraordinary.
  1887, Harriet W. Daly, Digging, Squatting, and Pioneering Life in the Northern Territory of South Australia, page 265