Final answer:
The word 'rate' in the sentence is a noun that refers to a degree or measure of something.
Step-by-step explanation:
The word 'rate' in the sentence 'Not at any rate until the songs have come true!' said they' is a noun. In this sentence, 'rate' is used to refer to a degree or measure of something. It is not used as a verb or an adjective in this particular context.
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