Adjectives ending with the letter W are listed in this post.
all-new
brand-new, bran-new, braw
callow, cash-flow, chow, chowchow, common-law
fallow, farrow, fellow, few, fire-new, fresh-new, frow
gewgaw
hebrew, highbrow, hollow
lew, low
meadow, mellow
narrow, new, now
overmellow, overslow
pay-per-view, peachblow, prow
raw, row
sallow, seesaw, shallow, shrew, siddow, skew, slow, southpaw, span-new
thorow, two-throw
undergrow, unknow
widow, wraw
yellow
Hope this word list had the adjective that ends in W you were looking for. Additional descriptive words can be found in the other pages on this site.
Please add more adjectives to make this list more complete: