No. It is not possible to use the CC functionality when sending emails from HubSpot. To include someone on an email in HubSpot, they must be added as a contact in the database and included on the sending list or as an individual recipient.
There is a feature called "Compliance Copy" that allows you to have specified email addresses receive a copy of every email sent to your list of contacts. Read more about this feature here, but please note that a copy of the email is sent to that email address for each recipient, so if you send your email to 1000 contacts, the person setup on the compliance copy will receive 1000 copies of the email.