First letter of the Greek alphabet (5)
I believe the answer is:
alpha
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">first letter of the greek alphabet</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for alpha that I've seen before include "Top grade" , "Greek vowel" , "leader in Athens, originally" , "European character" , "star of utmost brilliance" .)