Words like "anywhere" and "everybody" usually have a predefined or implicit context during conversations:
Everybody is going out to lunch. Would you like to come too? We are willing to go anywhere - we're starving.
In this statement, clearly the speaker doesn't mean all people from all places and times. When the speaker says he is willing to go anywhere, this isn't to be understood as a willingness to travel to Fiji for lunch, but instead is meant to be understood within an immediate context of the surrounding area, past experience with the hearer, or something else.
My touch-screen in my vehicle has a similar message when it's turned off:
Touch anywhere to activate.
Clearly it doesn't mean anywhere in the all-inclusive sense - touching my shoe won't turn the display on. There's an unspoken bit of information the reader is expected to understand. They would understand 'touch anywhere on this touch screen to activate this touch screen.'
What are these types of words called, if they even have a name?