If you are asking for language names:
Japanese
Jaquela
Jatapu
Javanese
Jawi
Jèrriais (Jersey Norman French)
Jingbu, Jtaszdasoten
Judeo-Arabic
Judeo-Spanish
Juǀʼhoan
Juhuri
Jurchen
If you are asking for grammatical terms:
(There are none)
Japanese
If you are looking for a native tree that starts with J , there is no J in the Maori language.
Noun
a jamprenia is an endangered bird
There is no J in the Hebrew language, except in modern, borrowed words.
Sorry, friend. Ukrainian language uses the Cyrillic alphabet, in which there is no J.
Joint and Juvenile Gas
· Jordan River (Israel, Jordan)
Debate Dissuasive speech
There are no geometry terms that start with the letter J. Geometry deals with the spatial relationships of objects.
Joule is a science term that begins with the letter j. A joule is a unit of energy required to perform a task.
There are hundreds of words that start with the letter j. There are less than 10 words in the English language that end with the letter j. There are no words that begin and end with the letter j.