Expect a holdup (5)
I believe the answer is:
await
'expect' is the definition.
(synonyms)
'a holdup' is the wordplay.
'holdup' becomes 'wait' (I can't justify this - if you can you should give a lot more credence to this answer).
'a'+'wait'='AWAIT'
Can you help me to learn more?
(Other definitions for await that I've seen before include "Look for (something to happen)" , "Stay around for" , "To be in store for (someone)" , "Hid a microphone in; bothered" , "Look forward to" .)