According to The Free Dictionary, the title is one of the meanings of the acronym NDM. Recently MathSciNet began to append the suffix NDM to the institution codes which it uses to indicate an author’s affiliation. So, instead of
1-SRCS: “This author is at Syracuse.”
you sometimes see
1-SRCS-NDM: “This author is at Syracuse. No disrespect meant.”
This change appears to be very recent (all papers with the -NDM suffix that I’ve seen were indexed in 2012) and its likely goal is to keep the unsuffixed codes, such as 1-SRCS, for the output of math departments only. MathSciNet long used the suffix -P for physics, as in 1-SRCS-P. But if physicists did not specifically mention their departmental affiliation, they could sneak in.
But no more! From now on, the lack of departmental affiliation marks you with the suffix -NDM, which I guess expresses the frustration of MathSciNet staff: “No Department, #*&$%*^!”. It is not to be confused with the code 1-NDM, which stands for Notre Dame math department. When the Notre Dame code acquires this suffix, is becomes 1-NDM-NDM.
Moral: to be admitted into the unsuffixed club, you must show your credentials, i.e., put your department in the author address field. Your name will not be enough, even if it is Terence Tao or Richard P. Stanley. No disrespect meant.