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

Buehler earned two All-Star selections and two World Series rings during his 10 years in the Dodgers organization, serving as a mainstay in their rotation whenever healthy and often looking like one of the majors’ top starters. —Los Angeles Times, 18 Feb. 2026

In just a few hours, the closing announcement attracted hundreds of comments and shares from devastated loyal customers who said the pizza has been a mainstay at local events since their youth. —Neal Riley, CBS News, 18 Feb. 2026

The mainstay of therapy is anticoagulation, commonly referred to as blood thinners. —Katia Hetter, CNN Money, 18 Feb. 2026

Muhammad, a native of the Dallas area, became a mainstay in the UT secondary. —Danny Davis, Austin American Statesman, 18 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