Bookplate (2,6)
I believe the answer is:
ex libris
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">bookplate</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I know that bookplate can be written as ex-libris)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for ex libris that I've seen before include "Bookplate inscription" , "Commemorative bookplate" .)