e/Ordinal collapsing function

Information
has gloss	eng: 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. For this reason, ordinal collapsing functions are described as an impredicative manner of naming ordinals.
lexicalization	eng: ordinal collapsing function
instance of	(noun) the number designating place in an ordered sequence ordinal number, no., ordinal