A mechanical pencil is a type of pencil that you don't have to sharpen with a sharpener. It has a small piece of lead inside that you can push out or retract using a button or twist mechanism. Full definition
For exams, I never liked to break from my routine of having three mechanical pencils at - the - ready because that is how I had always taken tests and had done well. (nourishing-matters.com)
Wide - set compartments keep everything, from thick markers to thin mechanical pencils, in place. (ourfamilyworld.com)
Her medium of choice is her beloved mechanical pencil. (creativeboom.com)