MM
millimeter, millimetre, mm
(noun) a metric unit of length equal to one thousandth of a meter
Source: WordNet® 3.1
Noun
mm
Abbreviation of month (in two-digit numeric format, as in: dd/mm/yyyy)
Interjection
mm
Alternative form of mmm
Noun
MM (plural MMs)
(education) Abbreviation of Master of Music.
(education) Abbreviation of Master of Management.
(freemasonry) Abbreviation of Master Mason.
(amateur radio) Abbreviation of maritime mobile.
Abbreviation of mile marker.
Abbreviation of man-month.
(philately) Initialism of mounted mint.
(finance) Abbreviation of million.
Noun
mM (plural mM)
(chemistry) millimole, millimoles
Proper noun
Mm
Abbreviation of masorah magna.
Source: Wiktionary