Here's parenting flashcard number 19 out of 50!
Petri dish n: a small child who brings home all manner of bacterium, virus, fungus, and/or protozoon to be spread indiscriminately via such vectors as runny noses, sticky hands, salival licks, and diaper changes - syn: sharer- see also: developing immunity, sick day, angry boss
used in a sentence: "It's not my fault I'm a petri dish."
My baby girl is 7 months old and I'm proud to say that she nor either myself or my husband have gotten sick once! I know the day shall come though!