What is unfreeze?

Some articles on unfreeze, unfreezes:

Tag (game) - Variants - Freeze Tag
... An unstuck/unfrozen player performs an action to unfreeze them, such as tagging them, crawling between their legs, or "flushing" them by hitting their outstretched hand ("Toilet tag") ... Variants exist where to unfreeze someone, the player must also call out a certain TV show ("TV tag"), sports team or object ... the thing can no longer be used to unfreeze someone ...
List Of Guest Stars On Futurama - Guest Stars
2 29 "Anthology of Interest I" ("The Unfreeze of a Lifetime") Gore, AlAl Gore Himself 29 ... "Anthology of Interest I" ("The Unfreeze of a Lifetime") Gygax ...
Theory of Heat Capacity - Energy Storage Mode "freeze-out" Temperatures
... degree of freedom there is a critical temperature at which the degree of freedom “unfreezes” and begins to accept energy in a classical way ... The rotational degrees of freedom are the next to “unfreeze" ... be spaced so widely that rotational heat capacity may not completely "unfreeze" until considerably higher temperatures are reached ...

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