Now, here is where the definition gets tricky: Thermos Mermos can be used as both a verb or noun.
Utilization as a verb states that Thermos Mermos is the act of refilling a thermos with excrement (must be diarrhea) so it's still warm when brought home to mother. Note that screaming "surprise" when the mudpies are found is and added touch to Thermos Mermos and does not have to be stated in all Thermos Mermos accounts.
Usage as a noun (Person): Thermos Mermos could refer to both the "actor" (person who fills the thermos with the shit-funnel) or the finder of the excrement inside the thermos.
Usage as a noun (Thing): A thermos with volcanic shit bubbling inside.
Nate: Why are you bringing your thermos to the bathroom?
Brian: I'm gonna Mermos this Thermos.
Nate: THERMOS MERMOS!