buy-to-let adjective 1noun 1buy to let verb 1forms 4 adjective1 •(UK) Describing, or relating to, a property bought as an investment, the purchaser letting it to others rather than living in it. noun1 •(UK) A property of this kind. buy to let verb1 •(UK) To purchase a property as in investment, and to let it out for rental instead of living in it formsbought to let · buying to let · buys to let · buy-to-lets