1. Jaded - bored or apathetic after experiencing too much of something
2. Jargon - technical terminology characteristic of a particular subject
3. Jaunt - a journey taken for pleasure
4. Jaunty - having a cheerful, lively, and self-confident air
5. Jeer - laugh at with contempt and derision
6. Jejune - lacking interest or significance or impact
7. Jeopardize - pose a threat to; present a danger to
8. Jest - activity characterized by good humor
9. Jettison - throw away, of something encumbering
10. Jibe - an aggressive remark directed at a person
11. Jingoist - an extreme bellicose nationalist
12. Jocular - characterized by jokes and good humor
13. Jollity - feeling jovial and full of good humor
14. Jostle - make one's way by pushing or shoving
15. Jovial - full of or showing high-spirited merriment
16. Jubilant - full of high-spirited delight
17. Judicious - marked by the exercise of common sense in practical matters
18. Juggernaut - a massive inexorable force
19. Juncture - a point in time when a critical decision must be made
19. Junket - a trip taken by an official at public expense
20. Junta - a group of officers who rule a country after seizing power
21. Jurisdiction - the territory within which power can be exercised
22. Jurisprudence - the collection of rules imposed by authority
23. Justify - defend, explain, or make excuses for by reasoning
24. Juxtapose - place side by side