n. A range of mountains.n. One who or that which ties.n. A child's apron. Also, erroneously, tire.n. In entomology, same as leaf-tier.n. A row; a rank, particularly when two or more rows are placed one above another: as, a tier of seats in a theater; the old three-decked war-ships had three tiers of guns on each side, the upper, middle, and lower tiers.n. In organ-building, same as rank, 1 .To pile, build, or arrange in tiers. Compare tierer.n. See tire.