This is an irregular feature - both in frequency and oddness - dedicated to a word I came across that I have never previously used.
dotard (DOE-tahrd) n. one whose intellectual capacity has been reduced by old age, disease, or injury; a foolish and doddering older person; a person in his or her dotage.
I came across this word while editing another writer's work, and I was convinced that this was a typographical error. Alas, it was not, and "dotard" is derived from the Middle English doten. This evolved into the modern term dotage, which is a state or period of senility marked by a decline in mental acuity and alertness.
I now have yet another term to describe my gradual descent from the seemingly unlimited intellectual powers I possessed as a carefree youth into the overloaded mental processors that are the hallmark of middle age.
I have been unable to locate a source that links "dotard" and the offensive "retard," but I suspect that these two words share some etymological roots.