A cascading biogenic pulse of thalaron radiation
A cascading biogenic pulse was a method whereby a form of radiation destructive to organic matter could be delivered in a highly-efficient burst of energy.
Such a method was utilized by Shinzon and his co-conspirators in 2379 to deliver deadly thalaron radiation with which to assassinate the Romulan Senate. Emitted from a small, hand-held generator planted by fellow conspirator Senator Tal'aura, the pulse was intense enough to kill all individuals in the Senate chamber. Shinzon later planned to use the same method to destroy all life on Earth utilizing the Reman Warbird Scimitar, which itself was, essentially, a massive thalaron generator, but was prevented from doing so by the crew of the USS Enterprise. (Star Trek Nemesis)
The use of the word "biogenic" indicates Thalaron radiation might be created from or created using biological matter, or a type of alien organism.