ANT: Disbelief, distrust, denial.
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KEY: Credential, or Credentials.
SYN: Missive, diploma, title, testament, seal, warrant, letter, vouchers, certificates, testimonials.
ANT: Self-license, Belt-constitution, self-appointment, autocracy.
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KEY: Credible.
SYN: Probable, likely, trustworthy.
ANT: Improbable, incredible, unlikely, untrustworthy.
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