hidden recipients
- blindLacking the sense of sight
- copyIdentical reproduction made
- emailDigital written communication
- undisclosedNot made known
- concealedMade invisible deliberately
anonymous · secret · private · recipients · envelope · carbon · forward · address · confidential · mass · mailing · list · invisible · covert · discreet · protected · sender · privacy
communication openness
hidden recipientspublic announcement
Official communication to all
open letter · broadcast message · mass mailing · public forum · social media post