nest egg
noun/ˈnest eɡ/
/ˈnest eɡ/
(informal)- a sum of money that you save to use in the future
备用的钱；储备金 - Over the years she had built up a nice little nest egg for her retirement.
多年来，她为自己的退休生活积累了一笔不错的存款。
- Over the years she had built up a nice little nest egg for her retirement.