Ridge
There are a few possibilities for this:
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">ridge</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for crest that I've seen before include "Top line of a hill, mountain, or wave" , "Summit - emblem - cockscomb" , "Highest point" , "Summit ridge" , "Top (of wave etc)" .)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">ridge</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I know that ridge can be written as ledge)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for ledge that I've seen before include "rocky situation?" , "Submerged underwater shelf" , "Narrow projecting shelf, on cliff or building" , "Projecting ridge on a mountain" , "Narrow shelf, often attached to window" .)
(Other definitions for shelf that I've seen before include "Ledge for holding things" , "Place for book -- or old spinster?" , "Horizontal surface for holding things" , "Ledge on which to stand items" , "Flat surface for holding objects" .)