Long-ago year? (3)
I believe the answer is:
dot
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">long-ago year?</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for dot that I've seen before include "Little girl" , "'Spot, tiny mark (3)'" , "Cotton, say" , "One of the signals in Morse code" , "Morse symbol; spot" .)