Clarification on geothermal heat pump terminology

[astronobri]

Hi, I'm relatively new to geothermal technology and I'm trying to understand what REopt is modeling with the water-source heat pump.

In the REopt User Manual (Pg. 91-92), it says one of the geothermal heat pump configurations is "Distributed water-to-air heat pumps (WAHP), or also described as water-source heat pumps (WSHP), are zone-level units that are coupled to the geothermal heat exchanger (GHX) with a building interior loop, sometimes called an ‘ambient’ loop. WAHPs ‘pump’ heat to and from the GHX fluid to deliver conditioned air to the zone to maintain zone temperatures."

I have seen the terminology "water-source" used interchangeably to mean the geothermal ground-source heat pump that has some kind of anti-freeze/water mixture running through plastic tubes in the ground (energy.gov website). But it sounds like REopt's "water-source heat pump" is not the geothermal ground-source system alone -- it sounds like the "water-source heat pump" in REopt means the water in the interior building loop that exchanges heat with the GHX fluid and also the air in the building. Am I understanding this correctly that these definitions of water-source are different between REopt and energy.gov? Thanks!