[sl-1]

I think in this case parasitoid has a specific meaning: https://en.wikipedia.org/wiki/Parasitoid

>Parasitoidism is one of six major evolutionary strategies within parasitism, distinguished by the fatal prognosis for the host, which makes the strategy close to predation.

[Terr_]

That sounds congruent with the "asteroid" example: It denoted a broad category, but eventually gained a very specific connotation, and when the connotation became popular enough, it took over as the new definition. So now we've got to use alternate phrasing like "starlike object" or "false star" or "pseudostar."

Terms like "spheroid" resisted the same fate, but I think that could change if everybody's talking a lot about some kind of spheroid that remains mysterious enough that we can't give it a better name in time.