Thrash refers to two disparate styles. While the term was first used to describe hardcore punk (and still is to some extent) it is commonly used as a shorthand for the unrelated and more popular style thrash metal.
Thrash metal: With its beginnings in the 1980s, it took inspirations from earlier extreme bands such as Venom and Hellhammer, NWOBHM, and hardcore punk. Various different offshoots have developed over the years (blackened thrash, Teutonic thrash etc.) as a result of the scene becoming saturated in the late ‘80s, although a recent resurgent of thrash metal bands is evident.
Thrash, a.k.a. thrashcore or fastcore: a fast tempo subgenre of hardcore punk that emerged in the early 1980s, often confused with crossover thrash and sometimes thrash metal influenced metalcore bands (when referred to as thrashcore). The -core suffix was added in the ‘90s to avoid confusion with metal, though the basic term ‘thrash’ still sees usage in reference to this style. .
