demising wall
A wall used jointly by two parties under easement agreement, erected upon a line dividing two parcels of land, each of which is a separate real estate entity; a common wall.
The tenants of 4A and 4B put up a demising wall to divide their previously contiguous apartment.
demising wall
A phrase used by pretentious architects, often incorrectly, to refer to a sound cancelling wall between two adjacent condominium units.
"Chuck decided to use the term demising wall on the project, be prepared to take questions about firing squads."