Green’s Dictionary of Slang

a well-off, middle-class Jewish teenager or young person, orig. just girls, usu. from North London, often collectively as becks.

2001		W. Self ‘How To Be An Economics Goddess’ in Indep. on Sun. 27 May 🌐 She even speaks with the slightly whiny tones of what we called – when I was growing up in Hampstead Garden Suburb – a ‘Beck’. This was short for ‘Rebecca’ and referred to the Jewish girls who hung around Golders Green bus station gossiping.
2024		J. Meades Empty Wigs (t/s) 140: No matter how vigorously you bang their mouths and their arses and their cunts the lazy Becks can’t be bothered to moan at the multiple pleasures I have afforded them.