This may be drifting away from the original question but here goes.
Own is a very general term indicating that one has legal rights in respect of property (which could be land, or physical items, or intellectual property etc)
It sometimes contrasts with possess which similarly can refer to many different kinds of property, but includes having property in one's care and / or use when it is owned by someone else; similarly if you lend property to someone else you own it but don't possess it.
Freehold and leasehold are technical terms used in respect of land (and perhaps a few other more obscure kinds of property).
At least in England and Wales since 1925,
- If you have a right to use land but don't have exclusive possession of it, you aren't a freeholder or a leaseholder, but have a license. This will happen if you rent a room in someone's house, but have no right to lock everyone else (including the owner of the house) out; or if you rent an office but the landlord comes in to clean etc.
In cases where you do have exclusive possession,
- If you rent land and under the agreement you agree to give the land back after a period (which can be one month or 999 years, etc), you are a leaseholder, not a freeholder. The same will happen if you buy leased land from an existing lessee (who obviously can only sell the remaining period of the lease)
- If you buy land and there is no obligation ever to give it back, you are a freeholder.
Janey has explained that the term freeholder is used loosely in the expression 40/- freeholder to include some kinds of leaseholder.
