Byte part (3)
I believe the answer is:
bit
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">byte part</span>' is the definition.<br/ ><span class="explanation-format__explanation">('bit' is part of 'byte')</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for bit that I've seen before include "Small fragment" , "scrap" , "Cutting head of a drill" , "Boring tip of a drill" , "Unspoken" .)