developed or executed with care and in minute detail; "a detailed plan"; "the elaborate register of the inhabitants prevented tax evasion"- John Buchan; "the carefully elaborated theme"
incapable of failure or error; "an infallible antidote"; "an infallible memory"; "the Catholic Church considers the Pope infallible"; "no doctor is infallible"
promise of reimbursement in the case of loss; paid to people or companies so concerned about hazards that they have made prepayments to an insurance company