The main difference between Scally and Chav is that the Scally is a family name and Chav is a A particular stereotype of anti-social youth dressed in sportswear.
Scally (also spelled Scales, Scully, Skelly, O'Scully, Scullin, Scullane) and "Scalaí" in Irish is a surname of Irish origin.
"Chav" ( CHAV) ("charver" in parts of Northern England) is a pejorative epithet used in the United Kingdom to describe a particular stereotype of anti-social youth dressed in sportswear. The word was popularised in the 2000s by the British mass media to refer to an anti-social youth subculture in the UK. The Oxford English Dictionary defines "chav" as an informal British derogatory, meaning "a young lower-class person who displays brash and loutish behaviour and wears real or imitation designer clothes". The derivative chavette has been used to refer to females, and the adjectives chavvy, chavvish and chavtastic have been used in relation to items designed for or suitable for use by chavs.
A rascal or miscreant, a scallywag.
A jobless yob who has little or no education and is suspected of having committed some type of crime.
A flat cap or driving cap.
A working-class youth, especially one associated with aggression, poor education, and a perceived "common" taste in clothing and lifestyle.