Parabolic paths (4)
I believe the answer is:
arcs
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">parabolic paths</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for arcs that I've seen before include "formations not straight" , "Curving trajectories" , "Parts of a curve" , "Curves in cars" , "Streaks of electrical discharges" .)