viscous
adjective
pools of viscous liquid had started to spread across the floor:
sticky, gummy, glue-like, gluey, adhesive, tacky, adhering, adherent, sticking, clinging, treacly, syrupy;
glutinous, gelatinous, thick, viscid, pasty, mucous, mucoid, mucilaginous, jelly-like, slimy;
informal gooey, gunky, gloopy, cloggy, icky;
North American, informal gloppy;
rare viscoid.
▷antonyms watery.