Overview
Unlike more general concepts of autology and self-reference, this particular distinction and opposition of "autological" and "heterological words" is uncommon in linguistics for describing linguistic phenomena or classes of words, but is current in logic and philosophy where it was introduced by Kurt Grelling and Leonard Nelson for describing a semantic paradox, later known as Grelling's paradox or the Grelling-Nelson paradox.
The fame of this paradox later extending also to non-academic circles has created a more widespread popular interest, expressing itself in more recent times also in the creation of lists of autological words.
One source of autological words are archetypal words (ostensive definition) – words chosen to describe a phenomenon by using an example of the phenomenon, which are thus necessarily autological. One such example is a mondegreen – a mishearing of a phrase, which itself is based on a mishearing of "And laid him on the green" as "And Lady Mondegreen".
A word's status as autological may change over time. For example, neologism was once an autological word but no longer is; similarly, protologism (a word invented recently by literary theorist Mikhail Epstein) may or may not lose its autological status depending on whether or not it gains wider usage.
Interestingly, non-autological words are sometimes playfully modified such that the new word becomes autological. Examples of such modifications include informal words like "ridonkulous" (saying the word "ridiculous" in a ridiculous way) and "ignant" (saying the word "ignorant" in an ignorant way). Words such as these are termed "synthetic autological words".
Read more about this topic: Autological Word