The word 'wonder' originates from the Old English noun 'wundor', which denoted a marvel or a miracle. This term is of Proto-Germanic descent, related to Old Saxon 'wundar', Old Norse 'undr', and Old High German 'wuntar', all sharing the core sense of something astonishing. The semantic journey is direct, moving from the concrete concept of a miraculous event to the abstract feeling of awe it inspires, and later to the verb meaning to ponder such marvels with curiosity. Its deep Proto-Indo-European root is uncertain but may be connected to concepts of smiling or pleasure, hinting at the positive astonishment inherent in the original meaning.

The word 'wonder' is a simplex word derived from Old English 'wundor', meaning a marvelous thing, a miracle. It is not productively segmentable into smaller, meaningful morphemes in modern English.