late Old English wunderfoll; see wonder (n.) + -ful. Related: Wonderfully.
Entries linking to wonderful
wonder n.
Old English wundor "marvelous thing, miracle, object of astonishment," from Proto-Germanic *wundran (source also of Old Saxon wundar, Middle Dutch, Dutch wonder, Old High German wuntar, German wunder, Old Norse undr), of unknown origin. In Middle English it also came to mean the emotion associated with such a sight (late 13c.). To be no wonder was in Old English. The original wonder drug (1939) was Sulfanilamide.
-ful
word-forming element attached to nouns (and in modern English to verb stems) and meaning "full of, having, characterized by," also "amount or volume contained" (handful, bellyful); from Old English -full, -ful, which is full (adj.) become a suffix by being coalesced with a preceding noun, but originally a separate word. Cognate with German -voll, Old Norse -fullr, Danish -fuld. Most English -ful adjectives at one time or another had both passive ("full of x") and active ("causing x; full of occasion for x") senses.
It is rare in Old English and Middle English, where full was much more commonly attached at the head of a word (for example Old English fulbrecan "to violate," fulslean "to kill outright," fulripod "mature;" Middle English had ful-comen "attain (a state), realize (a truth)," ful-lasting "durability," ful-thriven "complete, perfect," etc.).