dunno
"Dunno" is an informal, spoken shortening of "I don't know." It has just one meaning, but it's worth understanding because you'll hear it constantly in casual English conversation.
This is simply a very relaxed, fast way of saying 'I don't know.' When people speak quickly in casual conversation, 'I don't know' often gets squashed down into 'dunno.' You would never write this in a formal email or essay — it belongs in spoken conversation or informal text messages.
everyday language, informal speech · Modern, very common in casual spoken English