Entry 1 sense Webster, 1913 Confidentially /känˌ-fəd-ĕn'-shəl-ē/ · Con·fi·den·tial·ly · IPA /kˌɑnfədˈɛnʃəliː/ 01 adv. In confidence; in reliance on secrecy. 1. In confidence; in reliance on secrecy.