Jitterbug is a dance native to the United States. It starts with the letter j.
jacket jeans jersey
"Jacket" and "jumper" come immediately to mind, but there are likely others.
Besides the letter J itself, another letter that starts with J is junk mail.
a jar
Japan is an island that starts with J.
One Celebrity that's name starts with the letter "J" is Justin Timberlake.
Juice is a beverage that starts with the letter J.
There are no chemical elements that begin with the letter J.
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Your jaw starts with the letter J.
Joliet is a city in Illinois. It begins with the letter J.