Wikipedia lists ㄐㄧㄠˇ ㄗ˙ as the Bopomofo spelling for Mandarin jiaozi.
Bopomofo, also called Zhuyin, is a phonetic notation system used especially in Taiwan to represent Mandarin pronunciation. The spelling has two syllables: ㄐㄧㄠˇ represents jiǎo, and ㄗ˙ represents the neutral-tone zi in jiǎozi.
The tone marks are built into the symbols rather than written as separate accent marks. The third-tone marker ˇ follows ㄧㄠ in the first syllable, while the second syllable is shown without a full lexical tone mark because zi is commonly pronounced neutrally in this word.
The spelling is not a translation and does not identify a different dish. It is simply another way to record the Mandarin pronunciation of 饺子, the simplified Chinese form of jiaozi. Learners may also encounter the traditional characters 餃子 and the Hanyu Pinyin form jiǎozi, so the scripts can look very different while referring to the same dumpling.