When a female is at a state of arousal such that her vaginal secretions exit the vagina and begin to drip out of the vagina and onto a surface (I.E. a bed, the floor, the bath). In terms of male drippers, it is when a man has ejaculated but the seminal fluid merely seeps out of the penis and falls onto a surface.
"John you know sally?" "That dripper?" "Yea! Well she completely soaked my bed!" "Dude, I knew she was always wet"
So, I was waiting for him to cum all over my face but when he ejaculated all the sweet man juice fell on the floor, needless to say, I was disappointed. I don't like drippers.