addenseo

ad-densĕo, ēre, and ăd-denso, āre (cf. Wagner ad Verg. G. 1, 248), 2 and 1, v. a., to make close, compact (very rare):

extremi addensent acies,

Verg. A. 10, 432 Rib.—In pass., of water, to become thick, to thicken:

aquam radice ea addita addensari,

Plin. 20, 21, 84, § 230.