from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. Originally, a social club and debating society at Eton College; now the body of college prefects.
- n. A popular classical music concert.
Origin uncertain. The OED suggests either from (lolli)pop ("because the meetings were held in the rooms of Mrs Hatton, who kept the lollipop shop"), or from Latin popīna ("cookshop"). (Wiktionary)
Shortened from popular (concert). (Wiktionary)