1.Definition: a central cohesive source of support and stability

"Faith is his anchor", "The keystone of campaign reform was the ban on soft money", "He is the linchpin of this firm"

Related Noun(s):anchor, backbone, linchpin, lynchpin, mainstay

Category: General

2.Definition: the central building block at the top of an arch or vault

Related Noun(s):headstone, key

Category: Objects