Pain in both sides for Jacob's missus (6)
I believe the answer is:
rachel
'jacob's missus' is the definition.
I can't judge whether this definition defines the answer.
'pain in both sides' is the wordplay.
'pain' becomes 'ache' (ache is a kind of pain).
'in' indicates putting letters inside.
'both sides' becomes 'RL' (abbreviation for left and right).
'ache' put inside 'rl' is 'RACHEL'.
'for' is the link.
Can you help me to learn more?
(Other definitions for rachel that I've seen before include "Heal RC of the girl" , "Second wife of Jacob" , "Woman" , "Female" , "Import illicitly" .)