Foundations (5)
I believe the answer is:
bases
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">foundations</span>' is the definition.<br/ ><span class="explanation-format__explanation">('base' can be a synonym of 'foundation')</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for bases that I've seen before include "On which things stand" , "Fundaments" , "Foundations" , "headquarters" , "Supporting layers" .)