Meaning of MASS in English
I. mass 1 W2 /mæs/ BrE AmE noun
[ Sense 1-2,5-6: Date: 1300-1400 ; Language: French ; Origin: masse , from Latin massa , from Greek maza ]
[ Sense 3-4: Date: 800-900 ; Language: Vulgar Latin ; Origin: missa 'sending away at the end of a religious service' , from Latin mittere 'to send' ]
1 . LARGE AMOUNT
a) [countable] a large amount of a substance which does not have a definite or regular shape:
The food had congealed into a sticky mass.
a high mass of rock
b) [countable usually singular] a large amount or quantity of something
a huge mass of data
c) masses of something British English informal a large amount of something, or a lot of people or things:
Masses of books covered every surface in the room.
2 . CROWD [singular] a large crowd
There was a mass of people around the club entrance.
The road was blocked by a solid mass of protesters.
3 . the masses all the ordinary people in society who do not have power or influence:
The trains provided cheap travel for the masses.
4 . the mass of people/the population/workers etc most of the people in a group or society SYN the majority :
The war is strongly supported by the mass of the population.
5 . CHURCH CEREMONY ( also Mass )
a) [uncountable and countable] the main ceremony in some Christian churches, especially the Roman Catholic Church, which celebrates the last meal that Jesus Christ ate:
What time do you go to mass?
morning/evening/midnight etc Mass
Will I see you at morning Mass?
say/celebrate Mass (=perform this ceremony as a priest) ⇨ ↑ High Mass
b) [countable] a piece of music written to be performed at the ceremony of mass:
Mozart’s Mass in C minor
6 . SCIENCE [uncountable] technical the amount of material in something:
The Sun makes up 99.9% of the mass of our solar system.
⇨ ↑ critical mass
II. mass 2 W3 BrE AmE adjective [only before noun]
involving or intended for a very large number of people:
a mass protest
weapons of mass destruction
the problem of mass unemployment
mass marketing/entertainment etc
a mass marketing campaign
Email has made mass mailings possible at the touch of a button.
III. mass 3 BrE AmE verb [intransitive and transitive]
to come together, or to make people or things come together, in a large group SYN gather
mass (something) behind/along/in etc something
Western reports say that troops have been massing in the region since December.
grey clouds massing behind the mountains
Both countries have massed troops along the border.
Longman Dictionary of Contemporary English. Longman - Словарь современного английского языка. 2012