mainstay

noun

main·​stay ˈmān-ˌstā 

plural mainstays

1

a

: a crucial or key part of something

Fish is the mainstay of their diet.

Tourism is a mainstay of the city's economy.

The mainstay of treatment for chronic hives of unknown origin is antihistamine medications.

—Mayo Clinic Health Letter

b

: someone or something that is a principal or reliable support or resource

Tourism is one of the city's economic mainstays.

Her immense pride in him and unquestioning support were among the few mainstays in his life.

—Robert V. Remini

2

: a ship's stay (see stay entry 1 sense 1) extending from the maintop forward usually to the foot of the foremast

Synonyms of mainstay

• anchor
• backbone
• pillar
• standby

Examples of mainstay in a Sentence

Fish is a mainstay of their diet.

My mother has always been the mainstay of our family.

Recent Examples on the Web

The show is in preproduction on a new season, with CBS mainstay Drew Carey (The Price Is Right) joining the series as host (previous seasons haven’t had one). — Rick Porter, HollywoodReporter, 30 Sep. 2026

Anyway, nobody knows anything, but here are the bookies’ odds for the winner as of this writing, according to British betting mainstay Ladbrokes. — Emily Temple, Literary Hub, 29 Sep. 2026

Ukraine's long-range drones have repeatedly targeted Russian fuel depots and industrial plants that are a mainstay of Moscow's economy and war effort. — CBS News, 28 Sep. 2026

Ukraine's long-range drones have repeatedly targeted Russian fuel depots and industrial plants that are a mainstay of Moscow’s economy and war effort. — ABC News, 28 Sep. 2026

Word History

First Known Use

15th century, in the meaning defined at sense 2

Rhymes for mainstay

• airway
• allay
• archway
• array
• ashtray
• assez
• astray
• aue
• away
• ballet
• belay
• beltway

Kids Definition

mainstay

noun

main·​stay -ˌstā 

1

: a large strong rope running from the maintop of a ship usually to the foot of the foremast

2

: a chief support

the mainstay of the family