The term 'FLAT LIVER' can be solved by the 6-letter word 'LESSEE'. A LESSEE is a person who rents or leases property from a lessor. This type of agreement is often used in real estate, where a tenant pays rent to a landlord for the use of a house or apartment. In other cases, a LESSEE may rent equipment or machinery from a lessor. The LESSEE is responsible for the upkeep and maintenance of the property or equipment during the lease period.