A mythical being taught to young
children as a fact. In American culture, Santa Claus, the Tooth Fairy, and the Easter bunny are the three primary Santoids. The Stork is a more minor one used to explain where babies come from.
People typically learn the truth, sometimes even from their parents, by 12. They learn that their parents placed the gifts under the
tree, took the tooth and replaced it with
money, hid eggs at 3 AM, and one night they got together and...you know.
The
name comes from "Santa" plus "-oid", meaning "Santa-like."
Some say that Santoids are used to allow
children to think critically and question everything.
Others say they are used as secular substitutes for Jesus, or as a way of commercializing Christmas/Easter. In the case of the stork, it is to protect their fragile developing psyches.
"Sinterklass is a Santoid that Scandinavians teach their
children. It is just like
Santa, except it isn't."
"In the minds of atheists, God is just a Santoid some people never grow out of."
"Monsters under the
bed. The Scary Santoid. By three, you go through nights of no sleep, but by 6, you realize it is just a coat."