he-bê-tyud • Hear it!
Part of Speech: Noun, mass (no plural)
Meaning: Mental dullness, lethargy of thought.
Notes: Hebetude is the noun for the rather archaic adjective hebete "dull, mentally slow", not often used any more—but it is still out there in really, really comprehensive dictionaries. If this word is too short for you, please feel free to substitute hebetudinous, which has the same meaning.
In Play: Hebetude is not quite stupidity; it is simply a mental slowness or dullness: "The mortician had captured on the face of M. T. Head that same expression of hebetude that characterized it in life." The real advantage of this word, however, is that its infrequency allows you to use it even in the presence of hebetudinous people, as in: "It is less your attitude that worries me, Dwight, than your hebetude." If Dwight is not hebetudinous, he will run to the dictionary and make sure to avoid making such an impression in the future.
Word History: Today's Good Word comes from Latin hebetudo "dullness, bluntness", the noun from hebe(t)s "dull (physically or mentally)". How Latin came upon this stem is a mystery since we do not find any related words in other Indo-European languages. Even English only borrowed it once, leaving us with nothing more to say about it. If you are still hungry for etymology, you might like the newly discovered etymology of the name of the US state of Idaho. (Today we thank a man totally lacking in what the word he suggested signifies, Will Strockbine, recently retired from the State University of New York at Stony Brook.)