The phrase "cabin class" refers to a section or class of seating arrangements on airplanes or ships that is more comfortable than economy class but not as luxurious as first class. Full definition
This includes access for everyone on your booking as well as friends / family on different bookings traveling in the same cabin class on the same flight. (upgradedpoints.com)
You'll notice even carry - on bags get a higher weight consideration with each bump up in cabin class. (upgradedpoints.com)
You can also change an existing award to a higher cabin class and just redeem the extra miles. (rewardexpert.com)