Definition of mainstay
1 : a ship's stay extending from the maintop forward usually to the foot of the foremast
2 : a chief support
Examples of mainstay in a sentence
Fish is a mainstay of their diet.
My mother has always been the mainstay of our family.
First Known Use of mainstay
MAINSTAY Defined for English Language Learners
Definition of mainstay for English Language Learners
: a very important part of something : something or someone that provides support and makes it possible for something to exist or succeed
MAINSTAY Defined for Kids
Definition of mainstay for Students
1 : the large strong rope from the maintop of a ship usually to the foot of the foremast
2 : a chief support <the mainstay of the family>
Seen and Heard
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