Sui generis
Sui generis (; ) is a Latin phrase that means "of its (his, her, their) own kind; in a class by itself; unique."
Miss Peregrine's Home for Peculiar Children
Otherwise known as "syndrigast" (a word meaning "peculiar spirit" in the Old Peculiar language, which is in turn the author's adaptation of Old English, or Anglo-Saxon language), peculiar folk are a branch of humanity possessing a second soul which manifests itself in strange ways such as abnormal characteristics and abilities commonly referred to as "peculiarities". Very rarely are peculiar children born to peculiar parents as the essence or gene of peculiarity often skips entire generations, making peculiar population vastly less than that of normal people.