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 ;