This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

• Lexulous
• Wordscraper
• Wordosaur

n. The personal state or quality of being trustworthy or reliable. Commonly regarded as a virtue.

n. The state or character of being trustworthy.

n. the trait of deserving trust and confidence

"His trustworthiness is therefore critical to his job performance, and to his employers, and he must be above reproach."

trait   

reliability   

responsibleness    creditworthiness    responsibility   

probity    faithfulness    dependability    genuineness    truthfulness    conscientiousness    credibility    resourcefulness    manliness    straightforwardness