Spank bank is a slang expression for a person's collection of visual memories that are projected onto the "movie screen of the mind" during sex or masturbation to heighten sexual arousal, such as memories of women or men, images from films, pictures one has seen, fantasy images, etc. From the slang term spank = masturbate.
To be "spank bankable" means to be attractive and/or alluring enough to be deposited in one's spank bank.
"Spank bank" can also refer to a person's porn collection.
Related slang terms with the same meaning:
- spank box
- spank fuel
- spank mag
- spank tank