A griping pain is a sudden, sharp pain in the stomach, the kind that comes in waves and makes you want to fold up. Doctors and older writers use griping this way: the belly feels seized, as if something inside were squeezing. The base word is gripe, a pain of that sort. Though actually, in everyday talk now, griping is more often the -ing form of a different use of gripe: to complain in a small, repeated way (“Stop griping”). That complaining sense is very common; the stomach sense is narrower and a bit old-fashioned, but it is still the meaning in phrases like a griping pain. Stress and spelling both matter, because gripping (with a double p, from grip) means “so exciting you cannot look away.”