Yes, jump is a Scrabble word!
...and is worth 15 points in Scrabble, and 20 points in Words with Friends
jump
Verb
1. Move forward by leaps and bounds
2. Move or jump suddenly, as if in surprise or alarm
3. Make a sudden physical attack on
4. Increase suddenly and significantly
5. Be highly noticeable
6. Enter eagerly into
7. Rise in rank or status
8. Jump down from an elevated point
9. Run off or leave the rails
10. Jump from an airplane and descend with a parachute
11. Cause to jump or leap
12. Start (a car engine whose battery is dead) by connecting it to another car's battery
13. Bypass
14. Pass abruptly from one state or topic to another
15. Go back and forth; swing back and forth between two states or conditions
Noun
1. A sudden and decisive increase
2. An abrupt transition
3. (film) an abrupt transition from one scene to another
4. A sudden involuntary movement
5. Descent with a parachute
6. The act of jumping; propelling yourself off the ground
What Scrabble words can I make with the letters in jump?
3 Letter Words
2 Letter Words