The World Health Organization defines diarrhea as the passing of liquid or watery stools at least 3 times in a 24-hour period. However, it is the consistency rather than the number of stools that is important. Frequent passing of formed stools is not diarrhea.
Breastfed babies normally passes loose or pasty stools. The mother can tell if her baby has an abnormal stool.
If stools contain blood or mucus, it is called dysentery. If diarrhea persists for 14 days or longer, it is called persistent diarrhea.