Laos in rebellion too! (4)
I believe the answer is:
also
'too?' is the definition.
(synonyms)
'laos in rebellion' is the wordplay.
'in rebellion' indicates an anagram.
'laos' is an anagram of 'ALSO'.
(Other definitions for also that I've seen before include "To boot" , "As well, in addition" , "Old" , "in accompaniment" , "an indication of more to come" .)