mEnglishOxford New American Dictionarym /em, ɛm / ▸ abbreviation 1 mare. 2 married: m twice; two d. 3 masculine. 4 (m-) [in combination] Chemistry meta-: m -xylene. 5 meter(s). 6 mile(s). 7 [in combination] (in units of measurement) milli-: 100 mA. 8 million(s): $5 m. 9 minute(s). 10 (in Germany) mark; marks. 11 middle. 12 (in prescriptions) mix. 13 modification of. 14 modulus. 15 molar. 16 month. 17 moon. 18 morning. 19 mouth. 20 noon. [from Latin meridies.] ▸ symbol Physics mass: E = mc2.