My! her lot could be maternal (8)
I believe the answer is:
'maternal' is the definition.
(similar in meaning)
'my her lot could be' is the wordplay.
'could be' indicates anagramming the letters.
'myherlot' is an anagram of 'MOTHERLY'.
(Other definitions for motherly that I've seen before include "Maternally protective" , "Nurturing and protective" , "Maternal - gentle" , "Caring, protective" .)