'Jove'. As in 'By Jove'. The word now sounds very archaic, but Jove is a two faced Roman God, and so when the expression first originated it may have been more shocking. Shakespeare refers to Jove on one occasion. In Othello I think. Oh, and 'Jesus' is often used as an expletive. I have know people shout 'Jism' when they're angry. It is a slang word for semen.
At a soccer game people shout "Kick it!". It begins with the letter k.
Jump is shouted. It begins with the letter j.
The candy that begins with J is Jelly Beans.
Jade is a color. It begins with J.
Johnstown is a city in Pennsylvania. It begins with the letter J.
A store that begins with the letter J in Michigan is the J Crew store.
At a sporting event you might shout "Keep it up" or "Kick it!" You might yell at your children saying "Knock it off!"
No county in the United Kingdom begins with the letter J.
Sheriffs wear a jacket. It begins with the letter j.
No word in the English language begins with U and ends with J.
Journey is the name of a music group that begins with "J".
Jasmine is a flower. It begins with the letter j.