The word 再度 is formed through the conceptual combination of its two component characters: 再, which means "again" or "a second time", and 度, which carries the core idea of "passing through" or "a measure/occurrence". When combined, they create a single notion where the sense of repetition from 再 is applied to the idea of a passing or an occurrence from 度, essentially picturing "to pass through again" or "for another measured instance to happen", resulting in the integrated meaning of "once more" or "a second time".