Magenta - One of the four process colours; also known as process red.

Makeready - All activities required to set up a press before production begins. Also refers to paper used in the process.

Mark Up - Using standard symbols and proofreaders' marks, to write instructions on copy or proof telling how it should be prepared or corrected.

Matchprint - 3M trade name for integral colour proof.

Matte Finish - Slightly dull finish on coated, lightly-calendered paper.

Metallic Ink - Ink containing powdered metal that sparkles in light
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Micrometer - Instrument used to measure thickness of paper.

Modem - Short for modulator/demodulator, a device that converts digital signals to analog tones and vice versa so that systems based on electronic memories can interface over telephone lines.

Multicolour Printing - Printing done in more than one ink colour.