A ball (formal dance) in which the dancers wear masks or fancy dress

(printing) A metal sheet used in offset printing for carrying ink onto the rubber printing form.

Misspelling of en masse.

plural of body mass index

A teacher in charge of a boarding house at a boarding school. / A teacher in charge of a sports house at a school.

plural of Old Master

A love letter / gushing praise

A region within a solid astronomical body that is of higher density than the surrounding material. / A lunar mare that has a greater density of rock than the surrounding area.

plural of Grand Master

The output of a mass spectrometer