Welcome Rahik and be sure I'll not stop till the end
Now with the letter J
jock
An athlete, particularly a male athlete; usually used to describe someone who is good at sports but not so good at school.
Example
Kenny is a real jock -- he plays football, baseball, basketball and hockey!
Etymology
The term comes from 'jockstrap', which is an athletic supporter (tight underwear) worn by many men when they are involved in sports.
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jump ship
To leave your job; to move from one situation to another.
Example
When the company announced that it was losing money, many of its employees jumped ship.
Synonyms
A 'ship' is a boat - so when you 'jump ship' you flee (or leave) the boat by leaping over the side
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jumpy
Definition
Nervous or apprehensive; afraid that something bad will happen.
Example
1)
I'm always a little bit jumpy when I walk by the graveyard at night.
2)
Rachel sure is jumpy today. I said 'hello' and she nearly hit the ceiling !
Etymology
To 'jump' means to move into the air by springing or leaping up, so someone who is 'jumpy' is on the edge of leaping into the air in surprise or fear.
Synonyms
jittery