Stands for Things Gwyneth Paltrow Would Say. A way of mocking Gwyneth Paltrow, who is known for being somewhat "holier-than-thou" and seems to love showing the world that her life is, in fact, better than everyone else's.
You may also see the Twitter hashtag #TGPWS.
-"Come join me on the deck - it was handmade by Buddhist monks from Alsatian tree branches! I was just about to enjoy a snack of organic, locally-sourced quail eggs before a three-hour yoga session."
-"That is such a TGPWS."