 [ Symptoms ] what are the chances of hivstd as std can transmit from infected person to uninfected person through mucous membrane [ Disease ] people routinely use the word  wouldiarrhea to refer to any type of loose bowel movement and that is not exactly accurate diarrhea refers to a bowel movement that is almost purely liquid it contains some small pieces of stool but it is mostly water fluid to be precise loose stool is a soft bowel movement that ranges in consistency from somewhat formed to very runny whereas the particles of stool material in diarrhea are small and few in a loose stool the particles of stool material may be good sized in a sample of diarrhea the main component is very water like in a sample of loose stool no matter how runny the main component is stool material i hope that clears things up wishing you well