(Mass) the liturgy or a celebration of the Eucharist, esp in Roman Catholic and Anglo-Catholic churches

a musical setting for the ordinary² (invariable parts) of the Mass that do not vary

a quantity of matter or the form of matter that holds or clings together in one body

in physics, the property of a body that is a measure of its resistance to having its speed or position changed when a force is applied to it, causes it to have weight in a gravitational field, and is commonly taken as a measure of the amount of material it contains

an unbroken expanse; a bulk

a mountain mass

a mass of colour

the principal part or main body

informal (in pl) a large quantity, amount, or number

a large body of people in a compact group

(the masses) (in pl) the body of ordinary people as contrasted with the elite

All the world over, I will back the masses against the classes — W E Gladstone

to assemble (usu homogeneous elements) into a mass

the massed pipe bands

to assemble into a mass

relating to or intended for the mass of the people

a mass market

participated in by or affecting a large number of individuals

mass suicide

mass murder

large-scale

mass production