Argyroxiphium sandwicense subsp. sandwicense, the Mauna Kea silversword, is a highly endangered flowering plant endemic to the island of Hawaiʻi (Big Island) of Hawaii. It is the crown jewel of the volcanic mountain Mauna Kea, from which it derives its English name. The Hawaiian name is ʻahinahina; it applies to silverswords more broadly. The Mauna Kea silversword was once common on the volcano, and extraordinary conservation efforts are being made to preserve the species.