The Collaborative International Dictionary of English v.0.48:

Tier \Tier\, n. [Perhaps fr. OF. tire, F. tire; probably of
   Teutonic origin; cf. OHG. ziar[imac] ornament, G. zier, AS.
   t[imac]r glory, ti['e]r row, rank. But cf. also F. tirer to
   draw, pull; of Teutonic origin. Cf. Attire, v. t., Tire a
   headdress, but also Tirade.]
   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]

   Tiers of a cable, the ranges of fakes, or windings, of a
      cable, laid one within another when coiled.
      [1913 Webster]