From Middle English thikkenesse, thiknesse, from Old English þicnes (“thickness, viscosity, density, hardness; obscurity, cloud, darkness; thicket; depth, a thick body, anything thick or heavy”), equivalent to thick + -ness. Eclipsed non-native Middle English crassitude (“thickness”) from Latin crassitūdō (“thickness”).
- (uncountable) The property of being thick (in dimension).
- (uncountable) A measure of how thick (in dimension) something is.
- The thickness of the Earth's crust varies from two to 70 kilometres.
- (countable) A layer.
- We upholstered the seat with three thicknesses of cloth to make it more comfortable to sit on.
- (uncountable) The quality of being thick (in consistency).
- Whip the cream until it reaches a good thickness.
- (uncountable, informal) The property of being thick (slow to understand).
- (the property of being thick in dimension): fatness
- (measure): depth
- (layer): layer, stratum
- (in consistency): density, viscosity
- (property of being stupid): denseness, slowness, stupidity, thickheadedness
- (in consistency): fluidity, liquidity, runniness, thinness, wateriness
- (property of being stupid): mental acuity, mental agility, quick-wittedness, sharpness