What does "tier" mean?

Tier: One who, or that which, ties.

Additional senses

  1. 2.A chold's apron covering the upper part of the body, and tied with tape or cord; a pinafore. [Written also tire.]
  2. 3.A row or rank, especially one of two or more rows placed one above, or higher than, another; as, a tier of seats in a theater. Tiers of a cable, the ranges of fakes, or windings, of a cable, laid one within another when coiled.

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