1. To pledge property or goods as security for a debt without surrendering ownership: Mr. and Mrs. Smith hypothecated their house to the bank for a loan because they needed to buy a car and did not have enough money to pay for it.
2. Etymology: from Latin hypothecare "to deposit" ; from Greek hupotithenai, "to put under, to deposit as a pledge"; from hypo-, "under" + tithenai, " to place".