Yes, that's correct! "One ton of refrigeration" is a term used to measure the cooling capacity of an air conditioning system. It is based on the amount of heat energy that needs to be removed to lower the temperature of one ton (2,000 pounds) of water by 1 degree Fahrenheit in one hour.
The term originated in the early days of refrigeration when ice was commonly used for cooling. It was found that to produce one ton of ice in 24 hours, approximately 12,000 BTUs (British Thermal Units) of heat needed to be removed from the water to freeze it. This became the reference point for cooling capacity, and the term "one ton of refrigeration" stuck even as technologies evolved.
So, to answer your question, 1 ton of refrigeration is indeed the amount of heat energy in BTUs removed in 1 hour by an air conditioner to achieve the same cooling effect as melting one ton of ice in 24 hours. Today, the term is more of a historical reference, as modern air conditioning systems come in a range of cooling capacities and are not directly tied to the production of ice.