Crossword Genius

Left the dishes to be carried by trainees (1,6)

Ross

I believe the answer is:

l plates

I'm a little stuck... Click here to teach me more about this clue!

But I can't explain it at all! Could you help me understand?

(Other definitions for l plates that I've seen before include "Warning signs" , "signs of inexperience" , "should encourage cautious respect" .)

I've seen this clue in the Sydney Morning Herald.
Want a hint initially instead of a full solution? Install my app