It's a metaphor for a 'mental state' that we could experience according to the Taoist sages, in which we move lightly through life as if we're floating.
She gathered her robe and leaped lightly up across a barrier rock and onto the climbing path that only the desert-trained could recognize in the darkness.
The door slammed behind him, and I saw him walk lightly down the street, swinging his malacca cane, and I felt grateful to Dr. Haberden for such an improvement.
What was it? Why couldn't she remember? She looked down at her small daughter, so lightly poised on the galloping pony and her brow wrinkled as a chill swept swiftly through her breast.