The growing prominence of online hate speech is a threat to a safe and just society. This endangering phenomenon requires collaboration across the sciences in order to generate evidence-based knowledge of, and policies for, the dissemination of hatred in online spaces. To foster such collaborations, here we present the Gab Hate Corpus (GHC), consisting of 27,665 posts from the social network service gab.ai, each annotated by a minimum of three trained annotators. Annotators were trained to label posts according to a coding typology derived from a synthesis of hate speech definitions across legal, computational, psychological, and sociological research. We detail the development of the corpus, describe the resulting distributions of hate-based rhetoric, target group, and rhetorical framing labels, and establish baseline classification performance for each using standard natural language processing methods. The GHC, which is the largest theoretically-justified, annotated corpus of hate speech to date, provides opportunities for training and evaluating hate speech classifiers and for scientific inquiries into the linguistic and network components of hate speech.