Self-absorbed person (9)
(Other definitions for egomaniac that I've seen before include "Obsessively self-centred person" , "Excessively self-absorbed person" , "he thinks "it's all about ME"" , "Abnormally egotistical person" , "One who's self-obsessed" .)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">self-absorbed person</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 egotist that I've seen before include "One who is concerned only with self" , "Self-interested person" , "What I want" , "Boastful person" , "Conceited and self-centred person" .)