The fur trader was Jedediah Smith, NOT Jebediah Smith. Jedediah would simply be a variant spelling, deliberate or accidental, of the Old Testament name
Jedidiah.
The form Jebediah has turned up on occasion in the USA since the Civil War. It is a name that blends
Jeb with
Jedidiah.
Jeb is originally a nickname for the Confederate general
Jeb Stuart, who was born
James Ewell Brown
Stuart. This is one of the first examples of a nickname being created from initials. Because of
Stuart's fame,
Jeb began to be used as a given name in the Southern USA, and some parents then expanded it to Jebediah, probably simply misremembering or mishearing the Biblical name
Jedidiah, which had
Jed as a common short form. This is one of the few examples where a blended name probably did come about "accidentally" through ignorance rather than being a deliberate creation.