This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
• Wordscraper
• Wordosaur

v. Present participle of mass.

n. A bringing together into a mass.

n. The act denoted by the verb mass.

n. The act denoted by the verb mass.

n. Same as massage.

"The massing is composed of volumes stepping down from north to south in terraces."

collective   

massed    masses    massing   

prayer   

the masses    longitudinal mass    mass of the holy ghost    mass for the dead    buccal mass    law of conservation of mass    law of mass action    high mass    levy in mass    lateral masses of the sacrum   

masses   

massed    massing    mass extinction   

sum    bulk    magnitude    body    size    assemble    aggregate    quantity    number    lump   

Alsace    Cass    Glass    Grass    Grasse    Jas    Nass    Pass    Ras    Tass   

Gaming   

form    body    weight    portion    structure    cloud    surface    force    line    wave