Called round family as the most senior (7)
I believe the answer is:
ranking
'the most senior' is the definition.
'ranking' can be an answer for 'senior' (thesaurus). I am unsure of the 'the most' bit.
'called round family' is the wordplay.
'called' becomes 'rang' (called on the phone).
'round' indicates putting letters inside.
'family' becomes 'kin' (synonyms).
'rang' going around 'kin' is 'RANKING'.
'as' acts as a link.
Can you help me to learn more?
(Other definitions for ranking that I've seen before include "Place among seeds" , "Status" , "Position in a hierarchy" , "Assigning a position to" , "Grading" .)