Penguin

Quoting John Ellis

"In the spring of 1977, Mike Chanowitz, Mary K and I wrote a paper on
GUTs predicting the b quark mass before it was found. When it was found
a few weeks later, Mary K, Dimitri, Serge Rudaz and I immediately
started working on its phenomenology. That summer, there was a student
at CERN, Melissa Franklin who is now an experimentalist at Harvard. One
evening, she, I and Serge went to a pub, and she and I started a game of
darts. We made a bet that if I lost I had to put the word penguin into
my next paper. She actually left the darts game before the end, and was
replaced by Serge, who beat me. Nevertheless, I felt obligated to carry
out the conditions of the bet.

For some time, it was not clear to me how to get the word into this b
quark paper that we were writing at the time. Then, one evening, after
working at CERN, I stopped on my way back to my apartment to visit some
friends living in Meyrin where I smoked some illegal substance. Later,
when I got back to my apartment and continued working on our paper, I
had a sudden flash that the famous diagrams look like penguins. So we
put the name into our paper, and the rest, as they say, is history."

From Wikipedia