A large, black dong, usually made of rubber, that has a very prominent dorsal vein.
She tried telling me she wasn't in the mood, but I caught her pounding her 'gin with the veiny in the bathtub.
An adjective normally used negatively to describe a person, place or thing that doesn't please you. This is in reference to enormous dick veins.
Person 1: Hey, did you watch So You Think You Can Dance last night?
Person 2: Dude, that show is so veiny!