For the purposes of sections 138 and 139—
an original or derivative under-lease;
an agreement for a lease where the lessee has become entitled to have his lease granted; and
a grant at a fee farm rent, or under a grant securing a rent by condition;
an original or derivative under-lessee;
the persons deriving title under a lessee;
a grantee under a grant at a fee farm rent, or under a grant securing a rent by condition; and
the persons deriving title under such a grantee;
an original or derivative under-lessor;
the persons deriving title under a lessor;
a person making a grant at a fee farm rent, or a grant securing a rent by condition; and
the persons deriving title under such a grantor;
"lease" includes—
"lessee" includes—
"lessor" includes—
"under-lease" includes an agreement for an under-lease where the under-lessee has become entitled to have his under-lease granted; and
"under-lessee" includes any person deriving title under an under-lesse.