reasonable endeavoursreasonable endeavours: commonly used in business contracts; ...: commonly used in business contracts; a reasonable endeavoursreasonable endeavours: commonly used in business contracts; ... clause in a contract requires a party to use reasonable endeavoursreasonable endeavours: commonly used in business contracts; ... to do something, such as meet a target or time deadline; the legal effect of such a clause will be to require the relevant party to make a reasonable effort to achieve that target or deadline, but the party will not be required to do everything possible to achieve it, or to take responsibility for matters outside their reasonable control; compare with best endeavoursbest endeavours: in the context of contractual obligations, ... clause.