Included in selfie staggering out of Spanish celebration (6)
I believe the answer is:
fiesta
'spanish celebration' is the definition.
(I've seen this in another clue)
'included in selfie staggering out' is the wordplay.
'included in' indicates a hidden word.
'FIESTA' can be found hidden inside 'selfie staggering out'.
'of' acts as a link.
(Other definitions for fiesta that I've seen before include "Public whoopee in Spain" , "Latin American celebration" , "A Spanish public celebration" , "Saint's day; carnival" , "(Iberian) religious holiday" .)