Drink in, assimilate (6)
I believe the answer is:
imbibe
<span class="explanation-format__ClueExplanation">I believe this clue is a double definition.<br/ ><br/ >'<span class="explanation-format__original">drink in</span>' is the first definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >'<span class="explanation-format__original">assimilate</span>' is the second definition.<br/ ><span class="explanation-format__explanation">(I know that assimilate can be written as imbibe)</span><br/ ><br/ ></span>
(Other definitions for imbibe that I've seen before include "Drink in - assimilate" , "Tope" , "Drink or absorb into mind" , "Quaff" , "Drink, take in" .)