tautological
definition
redundantly repetitive or circular in reasoning
example
His argument was tautological, repeating the same point without providing any new evidence.
synonyms
redundantrepetitivecircular
word origin — The word 'tautological' originates from the Greek word 'tautologos', meaning 'repeating what has been said', from 'tauto-' meaning 'the same' and 'logos' meaning 'word' or 'reason'.