Comparative form of blunt: more dull or less sharp; also means more direct and lacking tact.
From 'blunt' plus the comparative suffix '-er,' which compares two things. This follows the standard English pattern for one-syllable adjectives.
Interestingly, calling someone 'a blunt speaker' is often a compliment in Scandinavian cultures but an insult in more indirect cultures—the same word describes politeness oppositely depending on where you are!
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