Meaning of THICKNESS in English
n.1 the state of being thick.
2 the extent to which a thing is thick.
3 a layer of material of a certain thickness (three thicknesses of cardboard).
4 a part that is thick or lies between opposite surfaces (steps cut in the thickness of the wall).
Etymology: OE thicness (as THICK, -NESS)
Oxford English vocab. Оксфордский английский словарь. 2012