Mother, in parts, altered chart (4,3)

'chart' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.

'mother in parts altered' is the wordplay.
'mother' becomes 'ma' (Ma is another word for mother or mum).
'in' means one lot of letters goes inside another.
'altered' is an anagram indicator.
'parts' is an anagram of 'starp'.
'ma' put inside 'starp' is 'STAR-MAP'.

Can you help me to learn more?