De Jongh is pronounced dee YOUNG (in the U.S.). It's a Dutch name, and a variant of the epithet "de jong," which means the young, and was used as a means of distinguishing between two bearers of the same personal name (usually a son from his father). In Dutch, de Jongh is pronounced duh Yoang, where the de is pronounced with a very short vowel sound, and the Jongh is virtually indistinguishable from the yo in yogurt.