Lanaian adjective 1noun 1forms 1 adjective1 •Of or from the island of Lanai.The obtained Ar/Ar ages of 1.6 Ma for the Lanaian lavas are significantly older than ages previously obtained for this island. — 2008 noun1 •Someone from Lanai.An effort was made by Lanaians in 1950 to have the island itself made a county. — 1952 formsLanaians