[PhasmaFelis]

From the link: "It is commonly abbreviated as m or M; further MM [...], mm, or mn in financial contexts." Note the semicolon.

Also note that the only cited source additionally claims that "M" is often used to indicate one thousand, as in $60,000 = $60M, which for all I know may be true in the financial world but is definitely not true for anyone outside that world who wants to be understood.