There is currently no way to add a person as a true Bcc recipient to a meeting request. If you'd like to request the Bcc field be added to meeting requests in a future update of Outlook, submit a suggestion to Outlook User Voice.
If you'd like to prevent a person from showing up on the list of attendees to a meeting, you can add them as a Resource, but their name will show in the Location field for the meeting.
To add a recipient to a meeting as a resource
In the new meeting request, in the Show group, choose Scheduling Assistant > Add Attendees.
In the Resources box, type the name or email address of each person you want to receive a copy of the meeting, but not be listed as an attendee.
If you've already added them to the list of attendees, click to the left of their name and choose Resource (Room or Equipment) from the drop-down list.
Important: This will put the attendee's name in the Location field of the meeting request.
Finish filling out the meeting request as you normally would, and choose Send.