brutally

adverb ! Definition from Wiktionary (CC BY-SA). More about brutally at Wordnik → Where our words come from →

1. In a brutal manner; viciously, barbarically.
2. In a direct way that does not attempt to hide, disguise, or mask unpleasantness; directly.

   He was not an expert but he was brutally honest by saying he couldn’t help the customer find a solution.

3. Extremely.