A Meta SOP Class is a set of SOP classes for a DICOM service that can be negotiated and supported as a complete set. Meta SOP Class support of a device is specified in the DICOM Conformance Statements.
As an example, when a hardcopy film needs to be generated for a physician or another institution, one can use DICOM Print. A DICOM Print User will have to manage several objects like Print queue or film session object, film box object, image box object etc. Since all the appropriate SOP Classes (session, film box, image box and printer) must always be supported as a complete set anyway, one typically negotiates them all with what is referred to as a single Meta SOP Class.