I thought a jiffy is a slang term and the official term is centisecond as per this site:
http://www.simetric.co.uk/si_time.htm
Similiarly, the source for the most commong name in the world according to Mirriam Webster is Chang according to
http://216.239.57.104/search?q=cache...hl=en&ie=UTF-8
Just so you know, the source makes a huge difference. I think MW is quite a reliable source myself.
WG