cre·tin 
(kr
ēt
n)
n. Often Offensive 1. A person with cretinism.
2. A person considered to be foolish or unintelligent.
[French crétin, from Franco-Provençal, person with cretinism (formerly common in Alpine valleys because of insufficient iodine in the local diet), from Vulgar Latin *christiānus, Christian, human being, poor fellow, from Latin Chrīstiānus, Christian; see CHRISTIAN.]
cretin·oid′ (-oid′) adj.
cretin·ous (-əs) adj.