Costanoan

[kos-tuh-noh-uh n, kaw-stuh-]

noun

a family of eight languages, now extinct, spoken by American Indian peoples of coastal California: part of the Penutian stock.

any of the speakers of these languages, who formerly inhabited the coast and adjacent river valleys from San Francisco Bay south to Monterey Bay and Point Sur.

adjective

of or relating to Costanoan or the Costanoans.

Origin of Costanoan

< Spanish costano coast dweller (cost(a) coast, shore + -ano -an) + -an

Examples from the Web for costanoan

They probably had just left Costanoan territory, although, to be sure, the exact tribal boundaries are unknown.
The Aboriginal Population of Alameda and Contra Costa Counties, California|S. F. Cook
It is quite true that some of the tribal groups inhabiting this territory may not have been members of the Costanoan stock.
The Aboriginal Population of Alameda and Contra Costa Counties, California|S. F. Cook