Female pig (3)
(Other definitions for goo that I've seen before include "Sticky stuff or sickly sentiment" , "Sentimentality (sl.)" , "syrup" , "Substance that's viscous" , "Slime" .)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">female pig</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 sow that I've seen before include "She lives in 11" , "swine" , "Plant seeds for the pig" , "farm animal" , "Prepare farmland" .)