'Marine! Get moving, bud!' (9)
I believe the answer is:
germinate
'bud' is the definition.
(thesaurus)
'marine get moving' is the wordplay.
'moving' indicates anagramming the letters.
'marine'+'get'='marineget'
'marineget' with letters rearranged gives 'GERMINATE'.
(Other definitions for germinate that I've seen before include "Sprout - develop" , "(Of seeds) sprout" , "Mere giant (anag) - start to grow" , "Spring up" , "Start to grow - a regiment (anag)" .)