Simple Definition of mainstay
: a very important part of something : something or someone that provides support and makes it possible for something to exist or succeed
Full 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 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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