TIER, n. A row; a rank; particularly when two or more rows are placed one above another; as a tier of seats in a church or theater. Thus in ships of war, the range of guns on one deck and one side of a ship, is called a tier. Those on the lower deck are called the lower tier, and those above,the middle or upper tiers. Ships with three tiers of guns are three deckers.
The tiers of a cable are the ranges of fakes or windings of a cable,laid one within another when coiled.
Tier, in organs, is a rank or range of pipes in the front of the instrument, or in the interior, when the compound stops have several ranks of pipes.