Here's what it could potentially mean:
* Misspelling: It could be a misspelling of "blanked," which is a slang term for "damned" or "cursed." For example, "That blanged car broke down again!"
* Slang: It could be a regional slang term with a specific meaning.
* Made-up word: Someone might have made it up for fun or to create a unique effect.
To figure out the intended meaning, you'd need more context. For example, what was the sentence it was used in? Who said it?
Let me know if you can provide more information, and I'll do my best to help!