The rumbling in your stomach that you experience after eating a delicious bowl of PHO. This rumbling is followed by a swift but suttle walk to the bathroom in order to hide the fact from your coworkers that you are about to dump out.
Blake and Brian are walking back to work after eating PHO.
Brian: DAMN! that PHO hit the spot!
Blake: Yeam man. I already got the Pho Flow goin.