Progressing slowly (7)
I believe the answer is:
gradual
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">progressing slowly</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 gradual that I've seen before include "(Of slope) not steep" , "Bit by bit" , "By easy stages, not sudden or steep" , "Little-by-little" , "Happening slowly and by degrees" .)