As other have explained, "hold luggage" is another term for "checked-in luggage", and designates luggage that will go into the hold of the plane (which you check-in/drop at the departure airport, and claim at the arrival airport).
Easyjet allows you to pool your luggage allowance. From Easyjet's FAQ on Baggage:
Can I pool my hold luggage allowance with other passengers on my booking?
You can pool your total luggage weight allowance – across
items and across customers – but an individual item cannot weigh more
than 32 kg.
So, each passenger with two items of 20kg hold luggage has a total
weight allowance of 40kg. They could pool their luggage allowance by
bringing one bag weighing 23kg and one bag weighing 17kg.
Two passengers on the same booking, each with one 20kg item of hold
luggage, have a total luggage allowance of 40kg. So they could pool
their combined luggage allowance by bringing one bag weighing 22kg and
one bag weighing 18kg.
Note that the 32kg limit is a hard limit. They will not, ever, allow you to check-in/drop a piece of luggage weighing more than 32kg (for the safety of baggage handlers).
It's not clear whether you could have more pieces of luggage than the number booked even if it fits in the total allowance in terms of weight, but in your case (1 piece 27kg and another 11kg), 2 x 20kg will definitely allow you to check-in those two pieces of luggage.