Crossword Genius

Thought to have left out light meal (9)

Ross

I believe the answer is:

refection

'light meal' is the definition.
(refection can mean a light meal)

I cannot understand how the remainder of the clue works.

(Another definition for refection that I've seen is " Meal or snack".)

I've seen this clue in The Guardian.
Want a hint initially instead of a full solution? Install my app