m Syllabification: (m)Translate m | into French | into German | into Italian | into Spanish Definition of m abbreviation mare. (in Germany) mark; marks. married:m twice; two d masculine. Physics mass. (m-) [in combination] Chemistry meta-:m-xylene meter(s). middle. mile(s). [in combination] (in units of measurement) milli-:100 mA million(s):$5 m minute(s). (in prescriptions) mix. modification of. modulus. molar. month. moon. morning. mouth. noon. [from Latin meridies] symbol Physics mass:E = mc2m in other Oxford dictionaries Definition of m in the British & World English dictionary