WordNet sense 1 (fairly large):

sizable, sizeable

WordNet sense 2 (above average in size or number or quantity or magnitude or extent):

big, large

WordNet sense 3 (having ample fabric):

full, wide

WordNet sense 4 (more than adequate):

generous

WordNet sense 5 (affording an abundant supply):

copious, plenteous, plentiful, rich

WordNet sense 6 (present in great quantity):

abundant