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 artist is also a mainstay at some of fashion's biggest circuits. — Eleanor Jacobs, PEOPLE, 29 June 2026

The satire mainstay has faced legal roadblocks in taking over Alex Jones’s conspiracy theory juggernaut. — Scott Nover, Washington Post, 28 June 2026

Flag lowering and raising ceremonies, reciting the Pledge of Allegiance and the singing of patriotic songs remain mainstays at many summer camps today. — Derek H. Alderman, The Conversation, 26 June 2026

The blouson or workwear chore jacket is always a mainstay of menswear, but this season there is a wider offer in fabrics and colors — a pragmatic approach to wardrobing balancing commerciality and novelty. — Rhonda Richford, Footwear News, 29 June 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