Vault, bound (4)
I believe the answer is:
leap
<span class="explanation-format__ClueExplanation">I believe this is a double definition.<br/ ><br/ >'<span class="explanation-format__original">vault</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >'<span class="explanation-format__original">bound</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ ></span>
(Other definitions for leap that I've seen before include "as 1984 was" , "'Look before you . . . .'" , "Jump; type of year" , "Jump, spring" , "some years?" .)