Uniden XDECT 8055 Owner's Manual page 20

The table below shows the possible icons and what they mean. Since
the icons appear based on what you're doing with the phone, you
won't ever see all of these icons at the same time.
Icon
20
What it means
(Handset only) Received signal strength indicator.
The ringer is turned off: this handset will not ring when a call
comes in.
Answer Machine ON/OFF status
You have a voice message waiting (only available is you
subscribe to a voice mail service - see the section titled "Using
Voice Message Notification" on page 32).
Privacy Mode is on: no other handset can join your call.
(Handset only) The speakerphone is on.
The handset is using ECO (power save) mode. The ECO feature
is automatically activated during talk or intercom modes. See
"Automatic ECO (Power Save) Mode" on page 48).
(Handset only) T-coil mode is on. (See "Do you use a T-coil
hearing aid?" on page 44.)
(Handset only) The battery levels;
Level 3 (Full)
Level 2
Level 1
Level 0 (Empty)