What are some things in Japanese that start with J?

Answer 1

The Japanese alphabet is entirely different. It consists of sounds rather than what we in the West think of as letters.

There are Japanese characters that represent the three different sounds - ja, ju and jo - that exist in other languages. They are, respectively, these:

ジャ

ジュ

ジョ

The word for Japan in Japanese is 日本 and it is pronounced nee-hon.

There is no Japanese word that begins with J because J does not exist as a separate and distinct letter in the Japanese alphabet.