How much is a myriad?

[RetroWeeeb]

Okay, so I'm trying to do a calc involving a weapon which is stated to be able to "vaporize a myriad of seas". The issue is, how much should I assume a myriad to be? The classical definition of a myriad is a unit of 10,000, but last time I checked there weren't 10,000 seas on the planet so that can't be correct. So, in a case like this, what would be a reasonable estimation for the number of seas being vaporized?

 

[Thelastmlg]

I mean, that sounds like a hyperbole anyway, myriad can be both 10000 or countless.

Eithe use 10000 or all oceans on earth, or just one and assume the weapon just has a lot of ammo