I. thinner
comparative of thin
II. thin·ner ˈthinə(r) noun
( -s )
Etymology: thin (IV) + -er
: one that thins: as
a. : a volatile liquid (as turpentine) used especially to thin paint, lacquer, and cement to the desired consistency — compare diluent a
b. : one that adds thinners and driers to paste mixtures to make liquid paint or varnish
c. : one that pulls out superfluous plants or picks off superfluous buds or fruit to improve the crop