Dear Rotalsnart,
[quote]Rotalsnart wrote:
I don’t remember how I came across the term. I have seen it or heard people use it occasionally over the years, but not often.
[/quote]
Hmmm.
[quote]Rotalsnart wrote:
I live in Taiwan, and no, the term “jiba” is not that frequently used by Mandarin speakers here (at least I haven’t heard it very often).
[/quote]
Hmmm.
[quote]Rotalsnart wrote:
Well, the same dictionary entry that I cited above gives the following variants: “或稱為「雞疤」、「札八」” , and I have little doubt that other variants have been used to represent this term as well.
[/quote]
Yes, I noticed that.
The reason I asked is that I was skimming through a Chinese-English dictionary put out by Shanghai Jiaotong University’s press that I had downloaded a while back when I came across this:

I couldn’t make out the second character for the combination meaning “penis”. The scan isn’t exactly the clearest.
I figured the top part of the second character was “hair” but the bottom part?
“Eight”? Since it’s pronounced “ba1”?
Or the “cave” radical but then that would seem more appropriate for the female sex organ. 
But luckily the Zhonghua Zi Hai has the entry and with source. I guess it’s from a book on the “Jin Ping Mei” and not the “Jin Ping Mei” itself since there’s a “ci hua”?

Unless I’m mistaken and it is the full title of the “Jin Ping Mei”?
I then recalled that someone at the Forumosa forum had mentioned “ji ba” being a colloquialism in standard Chinese (Mandarin) for “penis” and did a forum search.
You hadn’t given the characters but I didn’t think these were the characters since they’re rather rare. I think in Unicode Extension B.
I didn’t try looking for the characters myself seeing as there are so many characters with a pronunciation of “ji1”.
More than 50 in The Far East Chinese-English Dictionary alone.
Maybe if I had a dictionary that’s strictly alphabetical like the ABC series but then I don’t so that is of no use. And if I did have a copy, I doubt such rare characters would be there.
And I didn’t feel like going through each character and seeing which of the compounds it might be.
Anyway, you came back with 雞巴.
And according to the Hanyu Da Cidian, it’s also written with these two variants:

The variant way of writing “chicken” but also “ba” with the other “hair” radical on bottom.
Still I don’t know why these rare characters are in that dictionary. 
Since the only other dictionary to have the entry is the Zhonghua Zi Hai which purportedly has the largest number of unique Hanzi’s of any dictionary.
[quote]Rotalsnart wrote:
Still wondering what your “PLLA” stands for.
[/quote]
People always ask me that.
It’s kind of a jumbled acronym/abbreviation of where I’m at and an easy way for me to search for old posts of mine since my pseudonym is the name of a famous Japanese monk. It would return too many results in a typical search engine.
I guess I should have chosen an easy handle such as “translator” spelled backwards. 
Kobo-Daishi, PLLA.