On: 'Underwater bicycle' propels swimmers forward at s...

[riffraff]

That's a really odd mistranslation, given the Italian words for lightweight and light source are as different as in french (leggero/a vs luce). Looks like it was translated directly from the English content.

[eddd-ddde → riffraff]

It's so interesting how English tends to clump together so many concepts into the same word.