Where is it used? The name Mo is mainly used in English.
It is an abbreviated form of Maureen, used in Irish and in English. Maurice, used in English and in French. Moses, used in English and in the bible.
How do they say it elsewhere? Maurene (In Irish and in English) Moreen (In Irish and in English) Máirín (In Irish) Maurine (In English and in Irish) Mavreena (In Other languages)