Ablation (Def 1)
Medical
To remove or destroy a body part or tissue. This can be done in many ways, including surgery, radiation, or drugs
Ablation (Def 2)
Chemistry
The process of removing material from a solid surface by vaporization or sublimation
Ablation (Def 3)
Sci Rocket
The removal of material from the surface of an object by vaporization, chipping, or other erosive processes; used in heat shields to protect spacecraft during re-entry