v.1. To remain away from some surface or place: You should keep off the stairs; they might break.
2. To hold or maintain something away from some surface or place: Keep your dogs off my lawn.
3. To prevent something, especially something that is not wanted, from staying or accumulating on something: Try to keep those thoughts off of your mind. I've been exercising every day, but I can't keep the weight off.
4. To cause something to be nonoperational by having it remain switched off: I always keep the lights off when I look out the window at the stars. Keep off the lights to save electricity.
5. To refrain from indulging in something unhealthy, such as food or drugs: I've kept off cigarettes for three years now. Keep off of junk food and you'll lose some weight.