In this Part of this Act, except where the context otherwise requires—
"housing association" , "housing association tenancy" and "housing trust" have the meanings assigned to them by section 86 of this Act; and
"tenancy" means a housing association tenancy.
In this Part of this Act references to registration are, subject to section 87(5) of this Act and unless the context otherwise requires, references to registration pursuant to section 87.
It is hereby declared that any power of giving directions conferred on the Secretary of State by this Part of this Act includes power to vary or revoke directions so given.