nest egg

(noun) money saved up for the future or retirement

Example Sentences:

A: Do you have a lot of money in your savings account?
B: Yes, I have quite a big nest egg. I’m saving it up for a vacation in Cuba.

My father’s nest egg isn’t doing very well, because he lost money in the stock market.

From the Blogs:

Smart ways to crack your nest egg

Media:

Similar idioms:

1. a penny saved is a penny earned
2. have egg on one’s face
3. level-headed
4. bide one’s time
5. egg on
6. scrape by
7. don’t put all your eggs in one basket