When you want to give someone a standing ovation, but are too lazy to actually stand...most sitting ovations consist of people sitting, clapping, and clarifying that they are indeed giving a deserving person a sitting ovation, not just sitting and clapping; also called a sitting o.
lazy dude: encore, encore (claps hands while sitting)
rick: thanks, but your clapping is annoying.
lazy dude: dude I'm giving you a sitting ovation, you should be more appreciative of my support.
when one fists a fine young lady in both her vaginal and anal cavities and claps audibly
She gave me a standing ovation for my motivation speech. I gave her a sitting ovation for interrupting.