What is to hold the aforesaid real estate together with all the appurtenances and hereditaments thereunto belonging or in any wise appertaining unto the said party of the second part his heirs mean?

The phrase refers to the transfer of real estate ownership along with all associated rights and privileges. "Appurtenances" include any additional property or rights that come with the real estate, such as easements or water rights, while "hereditaments" encompass any property that can be inherited. Essentially, it indicates that the property and its benefits are being granted to the second party and their heirs.