bible verse
“Your neck is like an ivory tower. Your eyes are the pools of Heshbon by the gate of Bath Rabbim. Your nose is like the tower of Lebanon looking toward Damascus.”
meaning
Ivory tower is used as a term for isolation from reality.
origin and application
The word is commonly used to describe scholars who develop interests that are independent of the needs of the real world. But how this expression evolves from a simile of a neck to its present-day meaning remains unclear.
example
Some people viewed universities as ivory towers.