Pen pencil means: An Indian English term for a mechanical pencil - the kind with a thin lead that clicks or twists out of a metal or plastic barrel rather than needing sharpening. The name reflects a common naming. It is mainly Indian English and may not be understood outside that context. It has drug-related associations; worth a calm conversation about which side of the topic your teen is on. It is an education-system term, so usage is institutional and routine.