Loop in secretly

• Include secretly, as in an email exchange
• E-mail abbr
• Secretive email option
• Include discreetly, in a way
• Abbr. atop some e-mails
• Private email attachment, briefly
• Secretly keep in the email loop, for short
• Secretly email
• Include surreptitiously, in a way

Wiktionary Word definitions in Wiktionary
init. 1 body-centered cubic 2 blind carbon copy vb. to send something by blind carbon copy