In discussions about the meanings of words I often find participants bring up the etymologies as though they are conclusive deciding factors.
On the other hand there is concept of the "etymological fallacy" as discussed in Wikipedia.
The etymological fallacy is a genetic fallacy that holds that the present-day meaning of a word or phrase should necessarily be similar to its historical meaning. This is a linguistic misconception, and is sometimes used as a basis for linguistic prescription. An argument constitutes an etymological fallacy if it makes a claim about the present meaning of a word based exclusively on its etymology.
An etymological fallacy may involve looking for the true meaning of words by delving into their etymologies, or claiming that a word should be used in a particular way because it has a particular etymology.
Which is true? Or is the truth somewhere between? If words change over history how relevant is their origin to their current meaning? If the etymology of a word is a trump card which can settle debates about correct usage of words, does this mean words cannot in fact change over time?