In simplest terms, a trans het hypo red monster is a brick red colored which is slightly darker than brick red and reflective scales which is able to reproduce offspring like it.
Trans in reptile description stands for translucent scales. Translucent objects are objects that allow light, but not detailed shapes, to pass through. The scales of translucent reptiles would appear semi-transparent.
Het represents heterogeneous which means that the animal carries one of two genes needed to produce a desired trait and looks like a wild type, in this case the trait is the red appearance which is the main mark of the red monsters.
Hypo is short for hypo melanistic which implies that the reptile has less melanin and can appear slightly brighter.
A red Monster is a red scaled bearded dragon.