Mushy peas, chips and rocket (9)
I believe the answer is:
spaceship
'rocket' is the definition.
(thesaurus)
'mushy peas chips' is the wordplay.
'mushy' is an anagram indicator (letters mushed up).
'peas'+'chips'='peaschips'
'peaschips' anagrammed gives 'SPACESHIP'.
'and' acts as a link.
(Other definitions for spaceship that I've seen before include "Craft to travel outside the Earth's atmosphere" , "craft going far?" , "Craft for an astronaut" , "long-distance traveller?" , "long-distance vessel" .)