An irregular solid figure with 21 faces, 18 of them triangular and the other three square.

The craft of cutting white horses on hillsides.
The carousing of seamen on board Greenland whaling ships.
A person who bites his or her nails.
The process of becoming fat; fatness, obesity.
Five objects arranged so that four are at the corners of a square or rectangle and the fifth is at its centre.
Take a look at a dice (a die if you’re American), or the five of a suit of cards. In each case the dots or pips are arranged in this distinctive shape.
Habitual or obsessive nose-picking.
A substance that induces sneezing.