Alfilaria — every other issue is an affair (7)
I believe the answer is:
liaison
'affair' is the definition.
(synonyms)
'alfilaria every other issue is an' is the wordplay.
I cannot quite see how this works, but
'issue' could be 'son' (issue can mean someone's offspring) and 'son' is found in the answer.
'an' could be 'i' (Roman numeral for one) and 'i' is found within the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for liaison that I've seen before include "entanglement" , "Contact between groups" , "Fling - intrigue" , "Usually secretive or illicit relationship" , "sexual adventure" .)