Anywhoo, with apologies and declaration of availability for dating out of the way, today's word (one of my favourites!) is:
An arrangement of five things with four at the corners of a square and one in the middle. Most commonly seen in the pattern on cards (any 'five of something' and dice (five pips). Such a symbol was at one time used for the Roman fraction 5/12, thus explaining its etymology.
From Latin quincunx, from quinque five, and uncia a twelfth part.
To make up for last week's lack of wordiness, this week's usage comes in the form of a poem I wrote just for you fine people!
Johnny was a smart young lad,
Now Johnny's face is red.
When asked what five parts of twelve was called,
A 'quincunx,' Johnny said.
A gasp was heard by teacher dear,
Who gave not silent grace.
Poor Johnny, accused of cussing
Was slapped across the face!