A survey administrator is a special user that is allowed to access the LimeSurvey dashboard to create and prepare surveys.
You can refer to the following guide to define a survey administrator: How to enable a user for Surveys Management?.
There are currently two predefined roles for survey administrators:
Administrator of the application
They are not enabled to use the LimeSurvey dashboard, but they can instead grant access to internal users as Survey Administrators.
They can be defined from the application Management of Authorization and Groups.