Nouns

(n)thickening, thickenerany material used to thicken“starch is used in cooking as a thickening”
(n)node, knob, thickeningany thickened enlargement
(n)thickening, inspissationthe act of thickening

Adjectives

(s)deepening, thickeningaccumulating and becoming more intense“the deepening gloom”, “felt a deepening love”, “the thickening dusk”
(s)thickeningbecoming more intricate or complex“a thickening plot”