This IS advanced English, right?

Mortician (mor-tish'en) n. : an undertaker. Synonyms: guardian, parent.

Sample sentence: You can find a mortician at an orphanage.

Such was the definition that one group shared with the class. I let the definition slide initially because I thought I had simply mis-heard the group; then they read their sentence. At that point, I cut them off saying, "I hope you can't find a mortician at an orphanage, especially since they prepare people for burial!" Somehow my students-- sophomores in a Pre-AP class-- managed to confuse "undertaker" with "caretaker". Nevermind the fact that they had been given the root word "mort" along with its definition ("death" "dying"). So, why, oh why, did they assume that a mortician is a parent or guardian?

*sigh* Summer break can't come soon enough.