In dictionaries:
Collapsing pulse
Rapid rise and fall, palpable.
The Collapsing Empire
a space opera novel by American writer John Scalzi.
Ordinal collapsing function
In mathematical logic and set theory, an ordinal collapsing function (or projection function) is a technique for defining (notations for) certain recursive large countable ordinals, whose principle is to give names to certain ordinals much larger than the one being defined, perhaps even large cardinals (though they can be replaced with recursively large ordinals at the cost of extra technical difficulty), and then "collapse" them down to a system of notations for the sought-after ordinal.
collapsing rock sound
almost collapsing
collapsing in on itself
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