1.  tier(n = noun.state) grade, level - a relative position or degree of value in a graded group; "lumber of the highest grade"
is a kind of rank
has particulars: biosafety level, a level, gcse, general certificate of secondary education, o level, college level

2.  tier(n = noun.person) - any one of two or more competitors who tie one another;
is a kind of challenger, competition, competitor, contender, rival
Derived form verb tie₂

3.  tier(n = noun.person) tier up - a worker who ties something;
is a kind of worker
Derived form verb tie₁

4.  tier(n = noun.artifact) - something that is used for tying; "the sail is fastened to the yard with tiers"
is a kind of rope
Derived form verb tie₁

5.  tier(n = noun.artifact) - one of two or more layers one atop another; "tier upon tier of huge casks"; "a three-tier wedding cake"
is a kind of bed, layer

   One who, or that which, ties. [1913 Webster]

   A chold's apron covering the upper part of the body, and tied with tape or cord; a pinafore. [1913 Webster]

   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. [1913 Webster]

tier, n.
1 a row or rank or unit of a structure, as one of several placed one above another (tiers of seats).
2 Naut. a a circle of coiled cable. b a place for a coiled cable.

Derivative:
tiered adj. (also in comb.).

Etymology:
earlier tire f. F f. tirer draw, elongate f. Rmc

N  continuity, consecution, consecutiveness, succession, round, suite, progression, series, train chain, catenation, concatenation, scale, gradation, course, ceaselessness, constant flow, unbroken extent, procession, column, retinue, cortege, cavalcade, rank and file, line of battle, array, pedigree, genealogy, lineage, race, ancestry, descent, family, house, line, line of ancestors, strain, rank, file, line, row, range, tier, string, thread, team, suit, colonnade, continuous, continued, consecutive, progressive, gradual, serial, successive, immediate, unbroken, entire, linear, in a line, in a row, uninterrupted, unintermitting, unremitting, unrelenting (perseverence), perennial, evergreen, constant, continuously, seriatim, in a line, in succession, in turn, running, gradually, step by step, gradatim, at a stretch, in file, in column, in single file, in Indian file.

N  layer, stratum, strata, course, bed, zone, substratum, substrata, floor, flag, stage, story, tier, slab, escarpment, table, tablet, dess, flagstone, board, plank, trencher, platter, plate, lamina, lamella, sheet, foil, wafer, scale, flake, peel, coat, pellicle, membrane, film, leaf, slice, shive, cut, rasher, shaving, integument, eschar, stratification, scaliness, nest of boxes, coats of an onion, monolayer, bilayer, trilayer, lamellar, lamellated, lamelliform, layered, laminated, laminiferous, micaceous, schistose, schistous, scaly, filmy, membranous, pellicular, flaky, squamous, foliated, foliaceous, stratified, stratiform, tabular, discoid, spathic, spathose, trilamellar, graphitic.

tier up