Definition: In astronomy the word syzygy refers to three celestial bodies being in a straight or nearly straight line. A later definition also includes the three celestial bodies being in opposition. For example, when the earth is between the moon and the sun all three bodies form a syzygy. However, they also form a syzygy when the moon is between the earth and sun.
Pronunciation: sizz-igg-ee
Origin: From the Latin syzygia (“conjunction”), which is derived from the Greek syzygos (“yoked together”). It appears in English in reference to astronomy in 1847.
Why this word?
You are playing Scrabble and losing badly. You have no vowels, and that “sometimes Y” stuff is just not cutting it with these letters. A triple word score opens up and you realize that if you intersperse your consonants with y’s, you can spell ‘syzygy’, thus pulling ahead 75 points in scoring and earning the enmity of your family, along with their doubt that it is in fact a word. And that is when you can wow them with your amazing vocabulary and astronomical knowledge.
Additionally, the word syzygy is itself a type of syzygy, perfectly lining up three y’s. It is also the shortest word in the English language which contains three y’s. So that’s pretty cool.
How to use the word syzygy in a sentence?
In astronomical terms, syzygy refers to three celestial bodies being in a straight or nearly straight line.
“I think that I shall never see
A word as troubling as syzygy.
Though it may speak of celestial alignment
Speaking it’s a tough assignment.
The s and z, and then the g
Are in too close proximity
For tongues to tackle tactfully,
Too tight together to try, these three.
And having three (or just two) y’s
In such cramped space is none too wise.
Poems are made by fools like me
But only God can say syzygy.”
http://odock.blogspot.com/2011/12/syzygy.html