Spread through (7)
(Other definitions for overrun that I've seen before include "area beyond end of airstrip" , "Inundate, infest" , "Exceed (estimated cost)" , "Exceed (allowed cost/time)" , "Exceed (allowed time/cost)" .)
(Other definitions for suffuse that I've seen before include "Flood through" , "Of colour, spread slowly throughout" , "Spread; permeate" .)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">spread through</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 pervade that I've seen before include "Diffuse through the whole" , "Permeate" , "Spread throughout" , "Spread right through" , "Deprave (anag)" .)