[f. prec. vb. + -ER1.] That which (or one who) thickens; in Dyeing, a substance used to increase the consistence of the colors or mordants.
1652. French, Yorksh. Spa, iv. 46. The body is to be annointed with oyle, with spissaments or thickeners.
1732. Arbuthnot, Rules of Diet, in Aliments, etc., 261. Thickeners of the Humours.
1883. R. Haldane, Workshop Receipts, Ser. II. 206/2. The next step … is the removal of the thickeners.
