What does "still air" mean when planning alternative airports? When planning for a takeoff alternate, according to 14 CFR 121.617 


  (1) Aircraft having 2 engines. Not more than one hour from the departure airport at normal cruising speed in still air with one engine inoperative.


What does "still air" mean?

Is it because of the performance tables for Aircraft?

Or just don't take the effect of winds on aircraft range?
The latter - it means you don't need to take winds into account for that portion of the takeoff alternate selection.