Rotation refers to change in assignment and or location. It is usually used when people have to be sent to less then nice places, like the front lines, or to countries where they can't have their family with them. People are sent to these locations for certain periods of time, such as 18 months rather than a normal 2 year assignment.
turning
This is not used in the U.S. military.
Bronetransporter
To be forced into service
It means to be armed
secured area
It means a rotation of pi radians (180 degrees).
Extended combat training
Died While Missing
north Atlantic treaty organization
It is "Basic Active Service Date"
member of a State national Guard Unit