Absenteesim makes aunt cry terribly (7)
I believe the answer is:
truancy
'absenteesim' is the definition.
I can't tell whether this definition defines the answer.
'aunt cry terribly' is the wordplay.
'terribly' indicates anagramming the letters.
'aunt'+'cry'='auntcry'
'auntcry' is an anagram of 'TRUANCY'.
'makes' is the link.
Can you help me to learn more?
(Other definitions for truancy that I've seen before include "Failure to attend school" , "Unauthorised absence from school" , "bunking off" , "Staying away from school" .)