Sperm
To become or make stiff or stiffer.
Bandana
The nucleic acids DNA and RNA make up genetic material.
I think they enamel
Oak
iron rush
Thicker leather will be stiffer to begin with. To make a floppy leather hat stiffer, immerse it in boiling water, then shape it before it hardens. There are on-line instructions for this. Too much boiling, and the leather will become brittle.
mostly from cotton or nylon. Depends in what color you want it to be.
cloth wool and ect
Steel, metal, an very hot liquid from a boiler or something
Layers of natural or synthetic fabric in the construction of the carcass, more plies make the tyre stiffer.
Any kind of string-assuming you mean the game.