Initially find us in genuine denial (7)
I believe the answer is:
refusal
'denial' is the definition.
(I know that refusal is a type of denial)
'initially find us in genuine' is the wordplay.
'initially' suggests taking the first letters.
'in' is an insertion indicator.
'genuine' becomes 'real' (associated in meaning).
The initial letter of 'find' is 'f'.
'f'+'us'='fus'
'fus' put into 'real' is 'REFUSAL'.
(Other definitions for refusal that I've seen before include "Possibly first option to buy" , "regrets?" , "Indication of unwillingness (to do something)" , "Non-acceptance" , "Repudiation" .)