Freehold= as much ownership as one can hold (umlimited by time), subject only to the Crown's superior title.
Leasehold= ditto but limited by time (whether 999yrs. or one day!)
Head Lease (correctly used) = lease created by freeholder, esp. where there's an underlease too.
Underlease= lease created by leaseholder, usually for same period as leaseholder's Head Lease less the final x days.
You mention 'payment' but that's a consequence (not a definition). A lease/underlease reserves payments (from the person to whom it's granted) for:
a. 'ground rent'; and/or
b. service charge, if the person who grants it is responsible for delivery of services (e.g. block of flats: insurance, maintenance of common parts, etc.)
JEFFREY SHAW, solicitor [and Topic Expert], Nether Edge Law*
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