(brewing) a process in which part of the mash is removed and boiled and then returned WordNet 3.0 & Open English WordNet

In brewing and distilling, mashing is the process of combining a mix of ground grains – typically malted barley with supplementary grains such as corn, sorghum, rye, or wheat – known as the "grain bill" with water and then heating the mixture. Wikipedia

Process of combining a mix of grains with water and then heating the mixture. Wikipedia Disambiguation

The process by which something is mashed or beaten to pulp. Wiktionary