Wiktionary
n. A small tribe of Native Americans (diminutive of tribe); ''specifically''; small independent groups of Native California people which shared a language and usually comprised of one principal village - larger groups possibly having several villages all in close proximity.
Usage examples of "tribelet".
Galatian tribes and their tribelets came to Ancyra to answer the summons of Mithridates, looking more forward to the great feast they had been promised than to whatever projected campaign of mayhem and booty the sixth Mithridates was undoubtedly going to offer them.
For instance, California's native hunter-gatherers initially numbered about 200,000 in aggregate, but they were splintered among a hundred tribelets, none of which required a war to be defeated.
In addition, measles and some of our other "childhood" diseases are more likely to kill infected adults than children, and all adults in the tribelet are susceptible.