A selection of headlines from stories in the news. They use English in a way that you might think is intended to confuse, but it’s all perfectly clear to the native speaker.
Oi! Stop swanning off with our cress! is the headline in a Sun story about swans eating £250,000-worth of a farmer’s watercress crop.
If you “swan off with something” it means you take something in a relaxed way for pleasure and without caring that others may feel annoyed. Obviously these swans aren’t particularly bothered that the poor farmer is extremely annoyed.