The initial idioms of the letter J

jump up	jump with
jump at the opportunity (to do something)	jump the shark
jumped-up	puddle jumper
jumpy	jump
jump rope	jumping-off place
jumping-off point	jump-start
jump-start someone	juncture
jungle	jungle juice
jungle mouth	jungle telegraph
jungled	juniper juice
junk bond	junk food
junk heap	Junk it!
junk mail	junk squad
junk tank	junkyard dog
junk	junkie