Simple departure is without formality (9)
'is without formality' is the definition.
I can't judge whether this definition defines the answer.
'simple departure' is the wordplay.
'simple' becomes 'easy' (similar in meaning).
'departure' becomes 'going' (synonyms).
'easy'+'going'='EASY-GOING'
Can you help me to learn more?
(Other definitions for easy-going that I've seen before include "Placid; over-tolerant" , "Carefree - relaxed" , "Placid and tolerant, not strict" , "Hairdresser's shop" , "Happy-go-lucky" .)
(Other definitions for easygoing that I've seen before include "Calm" , "relaxed" .)