Following up on my earlier comment the following papers on euphemisms looked at least somewhat useful. I've sorted them in decreasing order of relevance ( not overall quality).
Swearing, euphemisms, and linguistic relativity
Doctors' use of euphemisms and their impact on patients' beliefs about health: An experimental study of heart failure.
Avoiding the term ‘obesity’: An experimental study of the impact of doctors’ language on patients’ beliefs.
Contamination and Camouflage in Euphemisms.
The connotations of English colour terms: Colour-based X-phemisms.
There's plenty of experimental work about how humans make poor judgments and decisions, but I haven't yet found much about how humans make poor judgments and decisions because of confusions about words. And yet, I expect such errors are common — I, at least, encounter them frequently.
It would be nice to have some scientific studies which illustrate the ways in which confusions about words affect everyday decision making, but instead all I can do is make philosophical arguments and point people to things like Yudkowsky's 37 Ways That Words Can Be Wrong or Chalmers' Verbal Disputes and Philosophical Progress.
Which keywords do I need to find experimental work on this topic? I tried Google scholar searches like "fuzzy concepts" "decision making" and effect of connotations on choices but I didn't find much in my first hour of looking into this.