lickety-split
Very fast or right away, with no delay.
Lickety-split means extremely fast, right away, or in a huge hurry. If your mom tells you to get ready for school lickety-split, she means immediately, with no dawdling or delay. If your dog hears the treat jar open, he'll come running lickety-split.
The phrase has a fun, energetic sound that matches its meaning. You might say “we finished our chores lickety-split” when you worked quickly and efficiently, or “the squirrel ran up the tree lickety-split” when it moved in a flash. It's more playful than simply saying “fast” or “quickly.”
Nobody knows exactly where this cheerful expression came from, but Americans have been using it since the 1800s. The phrase probably caught on because it sounds fast when you say it, with those sharp consonants clicking along. When you use lickety-split, you're adding energy and personality to your description of speed, making it clear that something happened in a snap, a jiffy, or the blink of an eye.