Parboil means to boil food partially. This term is used to refer the action to boil a food partially before it is going to boil actually at the time of cooking. Or you may define it as a limited time boiling than that of actual requirement. This method is particularly useful to eliminate poisonous or smelly-tasting substances from foodstuffs. This type of partial boiling is done in warm water. This is also a very time-saving technique. This helps intensively in stir-frying of different density food. You may parboil a high density food, say carrot and add it later in your cooking if you have shrimp as another ingredient for stir-frying. Using this method, you will be assured that cooking of all the ingredients will be finished at the same time without hampering any quality of any of them. This style of partial cooking is vastly used in various types of recipe, from rice to potato.