1. To move in an awkward or confused manner: Vance was about to blunder badly in his speech before he found the notes in the pocket of his jacket.
2. To stumble or to move clumsily: Miriam saw a stranger blundering across the street towards the coffee shop.
3. To act or to speak in a manner that is awkward, ignorant, or thoughtless: The child was so upset that she blundered to her teacher that someone had pushed her, which was not really true.
4. Etymology: from as far back as 1340, which came from Old Norse (Norwegian language as written and spoken from 100 to 1500) blundra, "to shut one's eyes"; while the oldest English sense was "to stumble around blindly". The meaning of "make a stupid mistake" is first recorded in about 1711.