-bo

   A diminutive ending used to create a double diminutive in Jimbo, ultimately from James. In a play broadcast on BBC radio in July, 1987, ‘Timbo’ was used as a double diminutive of Timothy. These examples may have been inspired by ‘Sambo’, the generic nickname used to a black West Indian or American, for which a Spanish origin is often claimed. Alternatively, the ‘ -bo’ ending shows a shortening of boy, since first name + ‘boy’ occurs fairly frequently as a term of address. ‘Sambo’ itself could easily have been a corrupt form of ‘Sam boy’: Sam was a common name amongst black slaves, as a perusal of Black Names in America, by Newbell Niles Puckett quickly reveals, and ‘boy’ was the normal term of address to any black male slave.