Deliver a tirade (4)
I believe the answer is:
rant
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">deliver a tirade</span>' is the definition.<br/ ><span class="explanation-format__explanation">(a tirade is a rant)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for rant that I've seen before include "bombast" , "Shout wildly at length" , "Rail" , "Talk wildly, rave" , "Talk wildly, harangue" .)