J
⟨jh⟩ is used in Walloon to write a sound that is variously /h/ or /ʒ/, depending on the dialect. In Tongyong pinyin, it represents /tʂ/, written zh in standard pinyin. Jh is also the standard transliteration for the Devanāgarī letter झ⟩ /dʒʱ/. In the official Esperanto orthography, it is a surrogate of ĵ.
⟨jj⟩ is used in Pinyin for /dʑ/ in languages such as Yi. In romanized Korean, it represents the fortis sound /tɕ͈/. In Hadza it is ejective /tʃʼ/.
⟨jö⟩ is used as a letter of the Seri alphabet, where it represents a labialized velar fricative, /xʷ/. It is placed between J and L in alphabetical order.
⟨jx⟩ is used in Esperanto as an unofficial surrogate of ⟨ĵ⟩.
Read more about this topic: Lj (digraph)