Photo of foxes by Keven Law
Shenanigans are the means used to make (possibly illegal) mischief by way of a rather complicated plot.
If a teacher found his pupils stacking up chairs so they could reach the ceiling of their classroom he might ask what are all these shenanigans?
If it was discovered that various people involved in a scheme had been meeting without telling one of the principals then they might be suspected of shenanigans, too.
Shenanigans is a marvellously vigorous word, and one whose origin has been argued over ever since it appeared in the 1850s.
It could be Spanish, German, Dutch or from a Native American language...
...but personally I don't think it's any of those.
Word To Use Today: shenanigan. This word comes from...well, no one's quite sure where it comes from. It first appeared during the California Gold Rush, and one problem is that as people rushed to the, er, Rush from all over the world, working out where the word shenanigan originated is jolly difficult.
However, as shenanigan is commonly used in Britain as well as the USA, by far the most likely thing is that the origin of shenanigan is Irish because there were plenty of hard-working and quick-talking Irishmen working in both California and Britain. Irish (Erse) also has the lovely word sionnachaíonn, from sionnach, fox, which means to fox someone, or to play tricks. So it's very likely, I think, that the first shenanigans were Irish ones.