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

• Lexulous
• Wordscraper
• Wordosaur

adj. Done or communicated in confidence; secret.

adj. Entrusted with the confidence of another: a confidential secretary.

adj. Denoting confidence or intimacy: a confidential tone of voice.

adj. Containing information, the unauthorized disclosure of which poses a threat to national security.

adj. kept secret within a certain circle of persons; not intended to be known publicly

adj. Enjoying, or treated with, confidence; trusted in; trustworthy.

adj. Communicated in confidence; secret.

Enjoying the confidence of another; intrusted with secrets or with private affairs: as, a confidential friend or clerk.

Intended to be treated as private, or kept in confidence; spoken or written in confidence; secret.

adj. entrusted with private information and the confidence of another

adj. (of information) given in confidence or in secret

adj. the level of official classification for documents next above restricted and below secret; available only to persons authorized to see documents so classified

adj. denoting confidence or intimacy

"Because keeping the supply chain confidential is so important to buyers, they try to impose confidentiality on their suppliers."

private    classified    close   

intimate    trusted    confidential communication    confidential relation   

confide   

trustworthy    secret    private    fiducial    fiduciary    trust   

consequential    credential    deferential    differential    essential    existential    experiential    exponential    inconsequential    inferential   

intimate    informal    diplomatic    urgent    friendly    unofficial    helpful    candid    trustworthy    lengthy