A morgue unit containing an incinerated Xindi-Reptilian corpse
A morgue unit was a storage compartment for keeping dead bodies in refrigeration, serving much the same purpose as a morgue, though a lot smaller. This type of technology had a control panel atop the unit, which could be used to open a drawer built into the unit.
In 2153, a morgue unit was used to store an incinerated Xindi-Reptilian corpse in a Starfleet hangar. Admiral Forrest opened the drawer in the unit so that he, Captain Jonathan Archer, and Vulcan Ambassador Soval could view the charred Xindi remains. (ENT: "The Expanse")
The term "morgue unit" comes from the final draft script of "The Expanse". In that teleplay, this type of technology was initially described as "a small, refrigerated morgue unit."