The overall groups are called Systems. The individual spaces in them are called Slots. The actual things that go in the slots are called Parts.
We do refer to parts as loot sometimes, but so far as I know it's only in the context of, well, them being loot. It's not their name, any more than your name is "the player," but it's referring to their role at that time.
In terms of "module" or "device," if it's referring to those as a non-proper-noun, then that's definitely something that needs to be corrected. But if it's like "Shield Module of Doom," that's just its actual proper-noun name.
Each entry in the part is generally referred to internally as an Effect, but I'm not sure that we actually bubble that up to the interface anywhere. When the line-item is on the bot itself, we simply refer to it as a Stat. So the effects are changes to stats, in other words.