Rowan is attested from the 1520s in the sense "fruit of the service tree", adopted via French "sorbe" from Latin "sorbum" "service-berry". "Sorbus domestica" is also known as "whitty pear", the adjective whitty meaning "pinnate". The name "mountain-ash" for "Sorbus domestica" is due to a superficial similarity of the rowan leaves to those of the ash, not to be confused in "Fraxinus ornus", a true ash that is also known as "mountain ash". "Sorbus torminalis" is also known as "chequer tree"; its fruits, formerly used to flavour beer, are called "chequers", perhaps from the spotted pattern of the fruit. The name
Mountain Ash, Rhondda Cynon Taf secondary school is the hospital Ysbyty Cwm Cynon which opened in 2012 replacing the old Mountain Ash General Hospital. Local primary schools include Our Lady's R.C Primary School, Caegarw Primary School (Ysgol Gynradd Caegarw), Glenboi Primary School (Ysgol Gynradd Glen-boi), Darranlas Primary School (Ysgol Gynradd Darren-las), Miskin Primary School (Ysgol Gynradd Meisgyn), Penguelan Primary School (Ysgol Gynradd Pengeulan) and Penrhiwceiber Primary School (Ysgol Gynradd Penrhiwceibr). Mountain Ash has a rugby union team called Mountain Ash RFC. Rugby league club South Wales Scorpions also currently play their home matches in Mountain Ash. Nos Galan (), is an annual running road race,