Use 'doozy' when something positively surprises you by being exceptionally good or impressive. I saw a Broadway show last night, and it was a doozy!
Pro Tip 2/3
Often Exaggerated
'Doozy' can be used to exaggerate the significance of something, making it sound more important. He scored a goal from the halfway line—it was a doozy!
Pro Tip 3/3
Not Formal
The word 'doozy' is casual and not used in formal writing or speech. You won't believe what happened at the party—it was a doozy!