Formally admit (6)
I believe the answer is:
induct
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">formally admit</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 induct that I've seen before include "Bring or lead in as for initiation" , "Formally admit (to a post or organisation)" , "Accept into an exclusive society or group" , "Introduce" , "Admit as a member" .)