Hide in Magaluf with Eco novel (10)
I believe the answer is:
camouflage
'hide' is the definition.
(I know that camouflage is a more specific form of the action disguise)
'magaluf with eco novel' is the wordplay.
'with' is a charade indicator (letters next to each other).
'novel' indicates an anagram (letters in a new or novel order).
'magaluf' after 'eco' is 'ecomagaluf'.
'ecomagaluf' with letters rearranged gives 'CAMOUFLAGE'.
'in' is the link.
(Other definitions for camouflage that I've seen before include "Method of blending in fine" , "Means of disguise" , "Green and brown on a green and brown background, say?" , "blind" , "Disguise by use of colour, patterns etc" .)