One's sis makes time for meeting (7)
I believe the answer is:
session
'for meeting' is the definition.
(session is a kind of meeting)
'one's sis makes' is the wordplay.
'makes' indicates anagramming the letters.
'ones'+'sis'='onessis'
'onessis' with letters rearranged gives 'SESSION'.
'time' is the link.
I am not very happy about this link. It may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for session that I've seen before include "Meeting, sitting, term" , "Studio recording period" , "Period devoted to an activity" , "Official sitting" , "Meeting devoted to a particular purpose" .)