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

But the galley’s focal point is its dynamic twist on the classic plate wall, a mainstay of traditional Southern decorating. — Betsy Cribb Watson, Southern Living, 7 Sep. 2026

The former Democratic speaker was the longtime villain, a mainstay in ads as Republicans linked Democratic candidates to her to paint them as radical and out of touch. — James A. Downs, The Washington Examiner, 6 Sep. 2026

The property partners with neighborhood favorites to offer premium lifestyle perks, including complimentary guest passes to the nearby Brooklyn Athletic Club, and exclusive discounts at local mainstays like SoulCycle and COS Williamsburg. — Condé Nast, Condé Nast Traveler, 5 Sep. 2026

And as tunnel fits continue to be a mainstay, NBA 2K27 made sure that plenty of apparel and streetwear brands were featured this year. — Riley Jones, Footwear News, 5 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