Introduce air into (6)
I believe the answer is:
aerate
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">introduce air into</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for aerate that I've seen before include "Send out, broadcast" , "Put bubbles into" , "Expose to fresh air" , "Introduce air into" , "Put air into" .)