When the consistency of your stools reflect a blended frappuccino from starbucks. Generally it refers to diarrhea, and can be preceded by the adjectives: Grande, Tall, or Venti to describe the size of the bowel movement.
A. Combination of frappe, cino, and -ish meaning a milkshake like drink originating in Italy with an unspecified taste.
B. Akin to tasting like the Starbucks moneymaker.