Definition of Tier

Noun: tier teer [N. Amer], tee-u [Brit]

A relative position or degree of value in a graded group
- grade, level
Any one of two or more competitors who tie scores with one another
A worker who ties something
- 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
"a three-tier wedding cake"; "tier upon tier of huge casks"