A cold treat akin to a popsicle. Freezies are made of a slushie-like juice that has been frozen in a long plastic wrapping. They come in many sizes, such as "jumbo," and the most popular brand in Canada bear(ed) the Mr. Freeze (pronounced "Free-zee") label.
Often, the best part about eating a Freezie was tipping the package upside-down and drinking the melted juice that was left at the bottom, when you'd finished eating the frozen part.
You could get a jumbo Freezie for, like, 50 cents at the ball park when I was a kid.