Caption
From SmartWiki
A Caption is the text used to identify a field.
In the case of a Built-in Field the caption can only be changed on External Pages.
For Custom Fields the caption property is used if you need to set a different label for the field than the field name. If the caption is not set, then the field name will be used as the caption.
See also
How do I display the field beneath the field's label/caption?
