mainstay

Plural: mainstays

Noun

• A principal support or part.
• a prominent supporter
• a central cohesive source of support and stability
• the forestay that braces the mainmast
• A chief support.
• Someone or something that can be depended on to make a regular contribution.
• A stabilising rope from high on the mainmast to the base of the foremast.

Examples

• Agriculture is the mainstay of this country’s economy.
• Vowel dumps are the mainstay of many desperate Scrabble players.

Synonyms

anchor, backbone, keystone, linchpin, lynchpin, pillar