classical

Classical means belonging to an established formal tradition. Classical music, classical architecture, a classical education.

In music it means the Western art tradition generally, and also, more narrowly, the period between the baroque and the romantic. In architecture and history it means ancient Greece and Rome — the classical world, classical studies. In physics, classical mechanics means the pre-quantum kind. Note classic, which is a different word meaning the best of its kind or the typical example, and which is constantly swapped for this one.