n.
a relative position or degree of value in a graded group
同义词：gradelevel
any one of two or more competitors who tie one another
a worker who ties something
同义词：tier up
something that is used for tying
"the sail is fastened to the yard with tiers"
one of two or more layers one atop another
"tier upon tier of huge casks"; "a three-tier wedding cake"
Fiscal Tiers: The Economics of MultiLevel Government
Tiers of Engagement by Universities in their Region's Development
Links: Web Programming Without Tiers
Links: Web Programming Without Tiers
Tiers in articulatory phonology: Some implications for casual speech
Tiers of ontology and consistency constraints in geographical information systems
Direct observation of tiers in the energy landscape of a chromoprotein: a single-molecule study
Papers in Laboratory Phonology: Tiers in articulatory phonology, with some implications for casual speech
The four tiers of structure in integrally skinned phase inversion membranes and their relevance to the various separation regimes
System for scheduling transmission of indexed and requested database tiers on demand at varying repetition rates
