"mainstay" in the noun sense
1. pillar, mainstay
a prominent supporter
"he is a pillar of the community"
2. anchor, mainstay, keystone, backbone, linchpin, lynchpin
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"
3. mainstay
the forestay that braces the mainmast
Source: WordNet® (An amazing lexical database of English)
Princeton University "About WordNet®."
WordNet®. Princeton University. 2010.
View WordNet® License