en masse

Main Entry: en masse
Part of Speech: adv
Definition: in a mass; all together; as a whole
Etymology: French
[ahn mas, en; Fr. ahn mas]
/ɑn ˈmæs, ɛn; Fr. ɑ̃ ˈmas/
1802, from Fr., lit. "in mass."
For example, The activists marched en masse to the capitol. This French term, with exactly the same meaning, was adopted into English about 1800.