Noun mainstay has 3 senses
- pillar, mainstay - a prominent supporter; "he is a pillar of the community"
--1 is a kind of supporter, protagonist, champion, admirer, booster, friend
- 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"
--2 is a kind of support
- mainstay - the forestay that braces the mainmast
--3 is a kind of forestay
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