From Caesar on Gaul: it's a wrap! (6)
I believe the answer is:
sarong
'it's a wrap' is the definition.
(I've seen this in another clue)
'from caesar on gaul' is the wordplay.
'from' indicates the answer is hidden within the clue.
'SARONG' is hidden within 'caesar on gaul'.
(Other definitions for sarong that I've seen before include "Brightly coloured skirt in the South Pacific" , "Draped garment" , "Malay cloth" , "Long Eastern garment" , "Loose skirt of the Pacific islands" .)