Y

Yarsanism = A syncretic, Monotheistic movement originating in Persia, for more info see Yarsanism. 
Yazidis = A Gnostic, Monotheistic movement with deep, historical roots. For more info, see Yazidis (external link). 
Yeshua = See the page for Yeshua. 
YHWH = Known as the 'Unspeakable Name,' this truly ancient Name was intoned only once a year, on the highest holy day of the ancient Israelites. Even then, only the high priest could speak it just once. Theists almost never use this name. Besides the fact that its exact intonation has been lost to time, every time a Theist does attempt to use it, something powerful and tremendous happens immediately afterwards. Both wonderful and cataclysmic, Theists have come to fear using this Name and reserve it only for truly dire circumstances.
According to legend, Lilith, mother of monsters and supposed first wife of Adam, was transformed into her current immortal state when she rebelled and uttered this Holy Name.
Youth Pastors = See Youth Pastor.