Topic Models Authors: David M. Blei, John D. Lafferty
The term topic and topic model refer to sets of highly probable words that are found to characterize a text.
The sets of words are called topics.
A topic model is the technique applied to a set of texts to extract topics.
In this particular article, latent Dirichlet allocation (LDA).
Apologies for the mis-use of the term topic but I suspect if we looked closely, someone was using the term topic before ISO 13250.
Good introduction to topic models.