How do scientists define temperature

A measure of the ability of a substance, or more generally of any physical system, to transfer heat energy to another physical system. The temperature of a substance is closely related to the average kinetic energy of its molecules.

I think-

Scientists define temperature with certain rules like the measure of the ability of a substance, or more generally of any physical system, to transfer heat energy to another physical system. The temperature of a substance is closely related to the average kinetic energy of its molecules.

Explanation:

a) the particles of the chair are strongly held together.

there are two significant figures.