An etymological fallacy is an argument of equivocation, arguing that a word is defined by its etymology, and that its customary usage is therefore incorrect.
Occurrence and examples
An etymological fallacy becomes possible when a word's meaning shifts over time from its original meaning. Such changes can include a narrowing or widening of scope or a change of connotation (amelioration or pejoration). In some cases, modern usage can shift to the point where the new meaning has no evident connection to its etymon.
Antisemitism The term antisemitism refers to hostility or prejudice against Jewish people, beliefs, and practices.. Extract from Islam in History: Ideas, Men and Events in the Middle East, The Library Press, 1973. It replaced the earlier term Jew-hatred. The etymological fallacy arises when a speaker asserts its meaning is the one implied by the structure of the word—racism against any of the Semitic peoples.
See also False friends
References
Further reading