I wondered myself why it's called that
and looked it up. The actual articulation trolley was patented in US In the early 19th century, apparently the name bogie was coined in in the late 19th century by a German engineer. I think the idea involved the bogie trolley being the actual coupler between 2 loads (a "jakobs bogie") with each load having its own rotating mount as opposed to one.
Eg..
.C1]_[C2......]_[C3......]
__O=O___O=O_____
But this was complicated to configure and needed lifting equipment. Also did not help the increasing weight issue, so rather than being a separate coupling unit I guess it made more sense for long carriages to bolt 2 sets on each all along.
I guess the bogie name just stuck
In UK it's the name we give to a booger too!
PS: Being from Europe, if someone said "train truck" as opposed to "train boogie" to me I would assume they meant a short wheelbase goods wagon like a coal cart rather than it's chassis, but I suppose that is exactly what a bogie is, a short wheelbase car just without anything on it