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oldcatholicguy
Guest
Not actually a source for the phrase having a primary meaning of “lying, lied” dating back to 1665 now is it. Perhaps the figure of three and half centuries was made up?The phrasal verb “make up”, like many phrasal verbs, has a variety of idiomatic meanings. When applied to an utterance of supposed fact, it implies dishonesty:
usingenglish.com/reference/phrasal-verbs/make+up.html