A
derogatory term that generally means "fool" or anything to that effect.
The latter, along with its other definition (which refers to a kind of bird), is defined in
dictionary.com, but, due to the fact that it seems to possess the
characteristics of a slang word, I felt that it would be useful if it was actually defined as a slang word.
In fact, it may have actually been an old English slang word, as an English person who I know was familiar with the term to a certain extent.
Also, it was used in a song in J.R.R. Tolkien's "The Hobbit" when Bilbo was trying to anger the giant spiders in the Mirkwood forest to lead them away so that he could rescue his companions.
Excerpt from Bilbo's song:
"Old fat spider
spinning in a tree! Old fat spider
can't see me!
...Old Tomnoddy, all
big body, Old Tomnoddy can't spy me!"