Take notice (4)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">take notice</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 heed that I've seen before include "Attend to, mind" , "Care, attention (paid)" , "Listen to carefully" , "Regard" , "Careful attention" .)
(Another definition for harken that I've seen is " Listen (archaic)".)