The recipient sees "unknown" or a blank field instead of the caller ID number.

It showed a blank field of dark bluish-gray with tinges of red.

The blank fields would include a small commentary, saying "this news was eaten by dogs".

Eviane knelt on a blank field of white.

When an image is presented to one eye and a blank field to the other, the image is usually seen continuously.

A blank field (Priority 3) indicates there is no known current or potential threat to the landmark.

The Mets posted a web poll to select a song, and left a blank field for write-ins.

It supported compression of blank fields in data using Run-length encoding.

There were all preformatted or 'canned' messages where the driver only needed to fill in blank fields and hit send.

They can have red lettering on a blank field (shubun) or the opposite (hakubun).