A Mexican second. This occurs when one says they will be "a second", but end up taking much, much longer. This is in reference to the sad tale of a man who went to Mexico for two weeks in order to get his condo fixed up, and none of the Mexican workers he hired showed up on time.
Sarah is getting ready for a date with Maxwell. Max arrives and Sarah tells Max,"Wait just a second." When Sarah is finally prepared, twenty minutes have passed. Max then comments cleverly, "Wait just a second? That was more like a smecond, Sarah!" And then they laugh gaily.