Without couth; lacking sophistication, refinement, or good manners; uncouth.
Formed from 'couth' with the suffix '-less' (meaning without), creating a word that circles back to meaning roughly the same as 'uncouth'—the word it came from.
Couthless is hilariously circular—you invented 'couth' as the opposite of 'uncouth,' but then you can add '-less' to it and get back to something uncouth means, showing how playful English word-formation can get.
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