Uso. It's a name. It's a laser, but they call it a disruptor. this is a different species, a different faction, with a different culture and different words. If they want to call it a disruptor, they can.
As for Doc talking about the SDR thing, He's just saying that a newer, lower tech race would not really be able to make a laser of that power, just yet. they simply do not have the technology for it, although that can probably be debated.
Also, Since when is the Dictionary wrong? I read the definition linked, and it is the proper one for what we're talking about here. just because its examples are not geared towards the cellular level does not mean the word cannot be used that way.