By definition of the KLI, a qepHom (pronunciation: S) is an informal meeting of at least 2 persons discussing the Klingon language, and maybe speak in it as well(1).
Meaning
The word itself is composed from the nounqepmeeting and the diminutive-Hom, so it means literally "small meeting". The word was formed as a counterpart to the name of the annual gathering of the Klingon Language Institute, the qep'a', which means "big meeting".
Usage
Although it was never defined as such, over the years a deeper meaning of the word developed, strenghtening an element of teaching. A qepHom therefore is always understood to be a beginners course as well.