Trope-a-Day: The Battlestar

The Battlestar: Several battlecruiser classes (see: Standard Sci-Fi Fleet) act as this sort of ship-of-the-wall/carrier hybrid, especially the ones specialized to go out on roving missions rather than hang around as fleet screening elements/participate in major actions.  Because specialized ships are almost always more efficient, except when your task force is too small to specialize ’em.  (Pure carriers are usually larger, in the same hull class as dreadnoughts or superdreadnoughts.)

Of course, what they carry are purely robotic AKVs, not manned space fighters, so they may not qualify as The Battlestar on that technicality after all.

There are also the giant lighthugger behemoths, the fleet carriers, whose job is to have an entire fleet of multiple squadrons, possibly including regular AKV-carriers, clamped on to them for near-c transport between star systems.  Since they are decently heavily armed against the possibility that – despite striving to avoid it – they may need to defend themselves while disembarking or embarking their fleet, they’re closer to the feel of the trope.  But much, much BIGGER.