A dictionary, but with dicks in it, so your standard high school dictionary.

when you've done something so cringe you can't stop replaying it in your head and it stops you from getting on with your every day life

n. reference book decribing types of male genitals including normal variants, congenital and acquired deformities,hermaphrodites, traumatic amputations etc.

a girls list of dateable guys by the size of their manhood.

This is the term given to any dictionary that is usually only read by assholes. Very popular in Congress.

when someone puts their dick into a book

A textbook which one utilizes when the male extremities of another are presented in a surprising fashion. The textbook is utilized to assess said appendage in categories such as strength, weight, and weight-to-strength ratio.