A (1) A deed (q.v.) in which a person undertakes to do or refrain from doing certain things, e.g. good behaviour bond. (2) Money paid to a landlord by a tenant at the start of a tenancy as security in case of future damage to premises or non-payment of rent. (q.v.) the object of which is to secure the performance of an act by the person bound by it, e.g. to be of good behaviour.