Comdial DXP, DXP Plus, FX Attendant Manual page 160

Glossary
U
Unscreened Call Transfer
Allows users to transfer line or intercom calls from one station or
group to another without first announcing them.
Unsupervised Conference
After a establishing a conference between two outside parties, the
originator drops out leaving a line to line unsupervised connection
with the remaining parties.
V
Voice call
A verbal intercom call.
Voice Announce Blocking (VAB)
A telephone can be set to block voice calls sent to it over the speaker.
Z
Zone Paging
Paging through the intercoms of some stations or departments in the
system.
150 Comdial August, 03