It is written throughout in majuscule Roman capitals, which, although MM.
This style is very important, as it marks the beginning of the change from majuscule to minuscule writing.
18c. (adj)., 1825 (n.), from French majuscule (16c.), from Latin maiuscula (littera), fem. of maiusculus "somewhat larger, somewhat greater," diminutive of maior (see major (adj.)).