Answer:
something that can be burned to produce heat
Explanation:
Combustion can be defined as an exothermic chemical reaction between physical substances, usually in the presence of oxygen and hydrocarbons to produce heat, light and carbon.
A fuel can be defined as something that can be burned to produce heat.
In the process of heat conduction, thermal energy is usually transferred from fast moving particles to slow moving particles during the collision of these particles. Also, thermal energy is typically transferred between objects that has different degrees of temperature and materials (particles) that are directly in contact with each other but differ in their ability to accept or give up electrons.