adjective / adverb / noun
thick
THIK/θɪk/
Having substantial depth between its surfaces.
The thick bread slice stands upright beside the loaf.

Etymology
Old English þicce covered both density and depth. The selected meaning preserves the depth side: a thick object has a substantial distance from one surface to the opposite one.
In context
4 m thick over large areas with ridges up to 20 m thick. One year ice is usually about 1 meter thick.
More examples
- The glass is half an inch thick.
- These thicker socks keep my feet warm.
- I slice the bread thick for French toast.
Forms
thick · thicker · thickest
thickness noun — The distance between an object's opposite surfaces.
thickly adverb — In a layer of substantial depth.
Similar words
- deep
- Measures inward or downward extent, rather than any opposing surfaces.
- chunky
- Suggests a thick, solid shape, often with short proportions.