Praxis has a P

I've not seen it in Star Trek, nor Star Wars. I've not read it in The Lost Fleet series nor has Honor Harrington dealt with it. OK, Babylon 5 had a small reference to it in a scene involving Garibaldi and Sinclair. However, "Praxis" by Walter Jon Williams, which I'm reading for Eastercon, has the following dialogue during an action sequence:

"“My lord?” Vonderheydte's query came into Martinez's headset. “May I have permission to use the toilet? I was drinking coffee while I was censoring the mail, and-”........
...... he didn't want the crew in Command to pee all over themselves either. “Who else needs the toilet?” Most of the hands went up. High gees were hard on bladders."