* A misspelling: Perhaps you meant a similar word like "derision," "de rien," or "deride."
* A foreign word: "Derien" could be a word from another language, such as French or Spanish. If you provide the context or origin, I can help translate it.
* A made-up word: It's possible "Derien" is a fictional name or term.
Please provide more information about where you encountered "Derien" so I can help you understand its meaning.