Elope with current partner being reasonable (10)
I believe the answer is:
legitimate
'reasonable' is the definition.
(thesaurus)
'elope with current partner' is the wordplay.
'elope with' becomes 'legit' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'current' becomes 'I' (symbol for electric current).
'partner' becomes 'mate' (synonyms).
'legit'+'i'+'mate'='LEGITIMATE'
'being' acts as a link.
Can you help me to learn more?
(Other definitions for legitimate that I've seen before include "Legal" , "It's admissible" , "Conforming to the law" , "Within the rules" , "In accordance with the rules" .)