In reply to The Potato:
The area covered by the new Central Wales climbing guidebook - basically from the Dyfi Estuary to the Brecon Beacons - is, as has been already said by several posters, the area normally considered to be Mid Wales.
In recent years and certainly within Wales, the revival of a very old name - Elenydd - has become increasingly common and is basically used to deliniate/identify the Cambrian Mountains area in Mid Wales. See: https://steepstoneclimbing.co.uk/guide
A deliberate decision was made to use Central Wales for the new guidebook rather than the more commonly used Mid Wales, as there was a Climbers' Club guide published in 1988, written by John Sumner, which was named 'Mid Wales'.
https://www.ukclimbing.com/logbook/book.php?id=148 Despite the title, the area covered by this 1988 guide was most definitely not what most people would identify as Mid Wales, not now nor actually even in 1988!
As an aside, the CC has shown a pretty poor understanding of Welsh geography in the past, so perhaps some climbers' current confusion is understandable .
Mid Wales' replacement by the CC was called 'Meirionnydd' (''Merioneth/ Merionethshire''), a local government area, now subsumed into Gwynedd, which has always been considered as North rather than Mid Wales. While this guidebook name was far more correct for most of the guidebook area, the CC still confusingly muddied the waters as Meirionnydd includes climbing in the Dolwyddelan and Betws y Coed areas (i.e. in Caernarfonshire, now Gwynedd) as well as in the Berwynion in NE Wales (i.e. in Montgomeryshire, now Powys).
The confusion continues as, more recently, the CC Pembroke North guidebook describes some of the climbing north of Llangrannog, which is actually in Ceredigion (i.e. Mid Wales), some 30 miles north of the county boundary of Pembrokeshire (i.e. South Wales).
Hopefully that's cleared it all up nicely.
Post edited at 12:15