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I'm dying for something cold to drink.
Literal
Cold thing [object-を] want-to-drink [uncontrollably-たまらない].
~たくてたまらない ('can't stand wanting to X, dying to X') is an intensified desire construction. ~たい ('want to') in て-form + たまらない ('can't stand, unbearable') = unbearable want. A vivid way to convey strong craving.