Made firm second date arranged with bombshell (8)
I believe the answer is:
steadied
'made firm' is the definition.
(I've seen this before)
'second date arranged with bombshell' is the wordplay.
'second' becomes 's' (common abbreviation).
'arranged' indicates anagramming the letters (letters rearranged).
'with' means one lot of letters goes inside another.
'bombshell' becomes 'die' (I can't justify this - if you can you should give a lot more credence to this answer).
'date' with letters rearranged gives 'tead'.
'tead' placed around 'die' is 'teadied'.
's'+'teadied'='STEADIED'
Can you help me to learn more?
(Other definitions for steadied that I've seen before include "Made firm and balanced" , "made stable" , "Braced" , "calmed down" , "Supported, controlled" .)