Lapse from this person in grasping maths ratio (6,3)
I believe the answer is:
venial sin
'lapse' is the definition.
(thesaurus)
'this person in grasping maths ratio' is the wordplay.
'this person' becomes 'I' (the person writing).
'in' is an insertion indicator.
'grasping maths' becomes 'venial' (I can't explain this - if you can you should believe this answer much more).
'ratio' becomes 'S/N' (S/N is an example).
'venial'+'sn'='venialsn'
'i' put inside 'venialsn' is 'VENIAL SIN'.
'from' acts as a link.
Can you help me to learn more?
(Other definitions for venial sin that I've seen before include "wrong, but forgivable" , "Minor offence against morality" , "Pardonable spiritual offence - not mortal" .)