Definition of well I'll be (or I'm) damned in English:

well I'll be (or I'm) damned

phrase

informal
  • Used to express surprise.

    ‘Well, I'll be damned! What brings you here?’
    • ‘Well, I'll be damned! What in tarnation are you doing in these parts?’
    • ‘Well I'm damned; you are quite right.’