When I want to comment code about control Enable/Disable and when I want to discuss with people about the control Enable/Disable, I really hope there is actually a word to it instead of typing or saying "Enable/Disable".
Currently I use the word EnDisable, what is the real word of it?
Really depends on the context.
Update: @Yacoby has the perfect one, it's widely used in user interface contexts.
If I'm writing functions that enable or disable something depending some other data, I usually call them "ToggleXXX".
I would suggest using "toggle" as although it doesn't exactly mean Enable/Disable it is commonly used as such in the context of user interfaces (as @Pekka mentioned).
Depends on the context. If you are referring to a life-support system, 'Kill' probably.