|Native to||California, United States|
|Region||Santa Cruz Island, Santa Rosa Island|
|Extinct||1915, with the death of Fernando Librado|
Cruzeño, also known as Isleño (Ysleño) or Island Chumash, was one of the Chumashan languages spoken along the coastal areas of Southern California. It shows evidence of mixing between a core Chumashan language such as Barbareño or Ventureño and an indigenous language of the Channel Islands. The latter was presumably spoken on the islands since the end of the last ice age separated them from the mainland; Chumash would have been introduced in the first millennium after the introduction of plank canoes on the mainland. Evidence of the substratum language is retained in a noticeably non-Chumash phonology, and basic non-Chumash words such as those for 'water' and 'house'.
- Heizer R. F., ed. 1952. California Indian linguistic records: The Mission Indian vocabularies of Alphonse Pinart. University of California Anthropological Records 15:1-84.
- Heizer R. F., ed. 1952. California Indian linguistic records: The Mission Indian vocabularies of H.W. Henshaw. University of California Anthropological Records 15:85-202.