Myslete stands fourteenth, writes m, and carries the numeral 40 from Greek mu. Its name is a Slavonic imperative plural meaning think or consider, one of three letter names in the alphabet that are commands rather than nouns.
The shape is the uncial mu, and in the early hands its middle strokes descend to the baseline in a rounded curve rather than meeting in a point, which is the feature that most reliably separates an eleventh century Cyrillic m from a modern one. The printed church types kept a form close to the manuscript letter; the civil type cut in the eighteenth century adopted the pointed shape used in Latin printing.
As a numeral it is 40, a number that recurs through the liturgical year: the forty days of the great fast, the forty days after a death, the forty martyrs. A reader of the church books meets this letter under a titlo more often than most.
The letter is also one of the commonest carriers of superscript abbreviation, standing above the line at the end of a contracted word, because Slavonic grammatical endings are full of it. Nothing about the letter changed as it passed into the modern alphabets, where it remains the ordinary sign for m in every Cyrillic writing system in use.