Noun

1. pillar, mainstay, supporter, protagonist, champion, admirer, booster, friend

usage: a prominent supporter; "he is a pillar of the community"

2. anchor, mainstay, keystone, backbone, linchpin, lynchpin, support

usage: 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, forestay

usage: the forestay that braces the mainmast

See also: mainstay (Dictionary)