Curved shape
'curved shape' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for ellipse that I've seen before include "See pill (anag) - oval" , "Geometrical oval" , "Inclined plane through a cone" , "Shape - sell pie (anag)" , "Egg-shaped geometrical figure" .)
'curved shape' is the definition.
(I know that crescent is a type of curved shape)
This is the entire clue.
(Other definitions for crescent that I've seen before include "Shape of waxing or waning moon" , "Waxing process could show one" , "Phase of the moon" , "Shape of new moon" , "Growing" .)