What does "to be a range of time shy of a date" mean? [closed]

Consider the following paragraph (Huffington Post):

Ronald Post died Thursday morning at a prison hospital where he'd been treated on and off since 2011, a state prisons spokeswoman said. He was a week shy of his 54th birthday.

What does the last sentence mean? What are its particular connotations?

Solution 1:

It simply means the death occured one week before he was to turn 54. See Def. #6 in Collins, which also mentions that that usage of the word is chiefly North American.

The term isn't only be used for ages and time; it could be used for other numerical amounts, too. For example:

I wanted to buy two tickets, but I was three dollars shy [of having enough money to purchase a second ticket].

I need to start dieting soon. My current weight is 4 pounds shy of my all-time high.

The heat wave continues in the west, with temperatures just a few degrees shy of breaking records.