1.)-prep. phrase- a polite, and usually deceptive, manner a man has to say that he is busy masturbating to orgasm.
Usually used in the presence of young children and/or parents/grand parents where one doesn't want to use the more obscene terminology, or otherwise wants to fly below the radar.
sometimes people can express things with their own words, for example, that expression above can be meant, to defecate, when you wanna do this action , you feel that you have something like a load you wanna unload it.