After a meeting is created you can always change the meeting label.
The terms meeting label and meeting title are used interchangeably and refer to the same thing.
Go to the meeting screen for the subject meeting.
On the left side of the screen, find the Meeting Data block.
Find the meeting label. If your access privileges allow you to change the meeting label, an Edit Meeting Label link appears below the label.
Click the link to display a text editor
Enter the new label and click the Update Meeting Label button.