Quakes (6)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">quakes</span>' is the definition.<br/ ><span class="explanation-format__explanation">('seism' can be a synonym of 'quake')</span><br/ ><br/ >This is all the clue.<br/ ></span>
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">quakes</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I know this)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for tremors that I've seen before include "The shakes" , "Small earthquakes" , "Vibrations" , "Quivering movements" , "Quivers" .)