It's possible that:
* It's a misspelling. There might be a similar word you're thinking of. Could you provide more context or information about where you encountered this word?
* It's a word from a specific dialect or language. If you know the language or region it comes from, it would be easier to understand the meaning.
* It's a made-up word. Perhaps it's a fictional term from a book, game, or other creative work.
Please provide more information so I can help you decipher the meaning of "ulkalu"!