[eesmith]

I had never heard of it either. https://en.wikipedia.org/wiki/At_sign

> The fact that there is no single word in English for the symbol has prompted some writers to use the French arobase[3] or Spanish and Portuguese arroba, or to coin new words such as asperand,[4] ampersat'[5] and strudel,[6] but none of these has achieved wide usage.

That Wikipedia entry start "ampersat", another term I hadn't heard of.

There's a lot of discussion on the talk page about the various names and neologisms.