Since `em quad' is hard to distinguish from `en quad', printers sometimes called it a `mutton quad'.
source: WordNet 3.0
a linear unit (1/6 inch) used in printing
source: WordNet 3.0
The portion of a line formerly occupied by the letter m, then a square type, used as a unit by which to measure the amount of printed matter on a page; the square of the body of a type.
