Jack
This is a pet form of John. It is now a very popular name in its own right. In the Middle Ages Jan evolved from John and then developed the pet form Jankin.
It was later shortened to Jack.

Joshua
From the Hebrew meaning the Lord saves. In the Old Testament Joshua succeeded Moses and finally led the Israelites to the Promised Land.

Jessica
No one really knows where this name came from, but it is thought it may well have been invented by Shakes-peare for his play The Mer-chant of Venice where Jessica was the name of Shylock's daughter. It is shortened to Jess or Jessie and is very popular at the moment.

Jake
A pet form of John, this is now a very popular name in its own right. In the Middle Ages Jan evolved from John and then developed the pet form Jankin, later shortened to Jack or Jake.

Jennifer
An old Cornish form of Guinevere, from the Welsh meaning white ghost and the name of King Arthur’s wife. It was hardly ever used until its 20th Century revival. It spread rapidly and was very popular in the 1950s and 1960s.

Jacob
This is a Hebrew name and the meaning is uncertain. In the Old Testament it was the name of Isaac's younger son. There were two Latin forms, Jacobus and Jacomus. Jacob came from the first and James from the second.

Joanne
This is the oldest female form of John and is a contraction of Johanna, the Latin feminine form of Johannes. The name came over from France in the second half of the 12th Century and by the 14th Century the name Joan had become the established form.

Jade
The name of the precious stone used as a first name.
Although the names of precious stones have been in use as girls’ names since the last century, this one seems only to have come into use in the 1970s and has been popular again recently.

Jasmine
A flower name also found in its normal botanical form, Jasmin.
The word comes from Persia (now Iran) and the name is also used in the Persian form Yasmin. It is currently growing in popularity

Joseph
From the Hebrew meaning the Lord added (to the family). In the Old Testament it was the name of Jacob and Rachel’s elder son who was sold into slavery in Egypt.
And, of course, it was the name of the husband of Mary, the mother of Jesus and also Joseph of Arimathea, who is believed to have buried Jesus.