This is a chemical reaction that absorbs heat from its environment
What is an Endothermic Reaction?
This is a type of reaction that requires external energy usually in the form of heat for it to reach completion.
Endothermic reactions and process are generally known to absorb heat from the environment thereby reducing the entropy change of it's surroundings. Endothermic reaction always end up with a positive value in change of enthalpy. Examples of endothermic process can be melting of ice, boiling of water etc.
For ever reaction to occur, it must be able to attain the activaton energy in order for bonds to break and new bonds to form. In exothermic reaction, this process is spontaneous and does not require external energy while for endothermic reaction, this requires external energy from the surroundinds in form of heat for these bonds to break.
In summary, this is a chemical reaction that absorbs heat from its environment