The term 'broach' can be defined by the following crossword solutions: INTRODUCE (9 letters), PROPOSE (7 letters), BEGIN (5 letters), OFFER (5 letters), PIERCE (6 letters), TAP (3 letters), OPEN (4 letters), and ADVANCE (7 letters). Broaching is a machining process that involves cutting or forming a hole in a workpiece. It is typically used to create internal features such as keyways, splines, and other forms of internal grooves. The process involves using a tool called a broach, which is a long, tapered cutting tool with multiple cutting edges. The broach is inserted into the workpiece and then advanced through it, cutting away material as it goes. This process can also be used to create external features such as holes and slots.