Karen Horney was a well know psychiatric patient of Abrahm, is this were the term 'Horny' comes from?

I thought that 'horny' had something to do with the word 'horn' being a slang term for....something naughty. Either that or the belief that powdered rhinoceros horn is an aphrodisiac...

The word horny 'sexually excited, lecherous' derives from an interesting yet not
surprising source. As early as the mid-18th century, an erection was known as a
horn or the horn, simply because it looked a bit like one. James Joyce even used
the term in his Ulysses. From there, any man having the horn was called horny,
and this is first recorded in 1889. It was surely in use long before then, as
the horn probably was. It often takes some time for lewd slang to make it into
the written record.
http://www.takeourword.com/pt.html