"mass spread" is correct and usable in written English.
You can use it to describe the process of something very quickly becoming known or accepted by a large number of people. For example, you could say "The new app quickly went viral, resulting in a mass spread of its popularity."
"Then someone would light a candle and its little flicker would show a strange human mass spread over the floor, sluggish and aching, rising in sudden convulsions, collapsing again".
CAMBRIDGE, MASSACHUSETTS Last night, an audience gasped and cheered as a slimy, yellow mass spread over Tokyo.
From curing cancer or solving the ongoing problem of climate change, to stopping the mass spread of fake news that can impact democracy and politics, these technologies are believed to be our golden ticket.
While preparing healthcare workers for dealing with infectious diseases and outbreaks is a concern, the mass spread of Ebola in the US is widely considered unlikely.
The modality of IF-RT administration was the following: (a) when the mass involved only the mediastinum, the whole original disease was irradiated; (b) when the mass spread beyond the mediastinum displacing the lung, IF-RT was administered to involve the mediastinum volume plus 1.5 cm outside its borders.
Cattle drives in westerns have taught moviegoers the beauty of the herd, a rippling organic mass spreading across the landscape like a bestial cloud.
After crossing the Mongolian Plateau, the air mass spreads southward and begins to invade North China, where it undergoes a series of rapid changes; its temperature rises slightly, and its stability decreases.
The mass spreading in to sub acute was of left hind leg out from the ventro-lateral of anus, 1.2 cm×1 cm/0 cm×0.5 cm in size and 125 g in weight.
The trapped water mass spreads over the bottom surface of the pipe for hydrophilic wall conditions, while it forms a compact lump when in contact with hydrophobic walls.
Just the fact that the vast Eurasian land mass spreads from east to west, while the continents of the Western Hemisphere spread from north to south, also limited the size of the cultural universe differently in the two regions of the world.
Although there is sufficient evidence to suggest that elevated fibrinogen levels might aid the development of metastatic lesions, we cannot ignore the possibility that this elevation is simply the result of the tumor mass spreading.
