The transferring party, who effects the transfer; he/she who transfers as asset and title (eg. sells their home or other property); usually synonymous with vendor or seller.
Property is transferred from the transferor to the transferee.
I sell you my house and in transferring title to you, I am the transferor and you, the transferee.
The forms used to record sales of real property or land with land title or registration offices or bureaus, will normally be signed at least by the Transferor, as it is this person who is transferring their recorded interest to another.
Here are two examples of the word used in legislation (with emphasis added):
"An instrument to transfer ... an interest in a lot ... must be executed by ... the transferor or the person creating the interest; and ... the transferee or the person in whose favour the interest is to be created."
NSW, Australia, Land Title Act, s. 166,
as of May 17, 2007.
"The signature of a transferor on an instrument is proof, in the absence of evidence to the contrary, that the transferor knows the contents of the instrument and has signed it voluntarily, and has the legal capacity to execute the instrument and intends to be bound by it."
BC, Canada, Land Title Act, s. 42(4)