Savings kept in reserve (4,3)
I believe the answer is:
nest egg
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">savings kept in reserve</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for nest egg that I've seen before include "reserves" , "Money saved for the future" , "Savings kept in reserve" , "Is it to encourage laying" , "Retirement savings" .)