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

What that means is the Super Bowl is increasingly being viewed by audiences who typically weren’t as significant for the more than half century the event has been a TV mainstay. —Brian Steinberg, Variety, 4 Feb. 2026

These spots bring in new advertisers outside of the mainstays like Budweiser and Lay's. —Lillian Rizzo, CNBC, 4 Feb. 2026

Whether its popular mainstays like Wingstop and Buffalo Wild Wings or more local favorites like La Figata and TJ’s Burritos, there are more than enough options to feed all your hungry guests for the big game. —Blaine Callahan, Hartford Courant, 3 Feb. 2026

For 11 seasons, DeMarcus Lawrence was a mainstay on the Dallas Cowboys’ defensive line. —Sportsday Staff, Dallas Morning News, 3 Feb. 2026

Word History

First Known Use

15th century, in the meaning defined at sense 2

Rhymes for mainstay

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

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