Jeeves
Jeevesy
Jeff
Jefferson
Jefferson Davis
Jeffery
Jeffrey
Jeffry
Jefrette
Jekyll
Jellaby (after the butler in Tom Stoppard's play "Arcadia")
Jellicle
Jellico
Jellifur
Jello
Jell-o
Jelly
Jelly Baby
Jelly Bean
Jelly Belly
Jelly Roll
Jelly-Belly
Jellylorum
Jemima
Jen
Jeners
Jenga
Jenna
Jennet
Jennie