Eg Hammerstein’s gigantic vehicle? (5)
I believe the answer is:
oscar
'eg hammerstein's' is the definition.
(lyricist Oscar Hammerstein)
'gigantic vehicle?' is the wordplay.
'gigantic' becomes 'os' (I can't justify this - if you can you should give a lot more credence to this answer).
'vehicle?' becomes 'car' (car is a kind of vehicle).
'os'+'car'='OSCAR'
Can you help me to learn more?
(Other definitions for oscar that I've seen before include "Hollywood statuette given as annual award" , "One close to Mike" , "academy's prize" , "letter read out on radio" , "feature of award ceremony" .)