〈名〉Performance; fulfilment:(=する) to perform, fulfil, keep, make good (one's promise)
◆約束を履行する to fulfil one's promise―keep one's promise―keep one's word―make good one's promise―redeem one's pledge
◆彼は立派に約束を履行した He was true to his word―as good as his word.
◆約束を履行しない He broke his promise―He was false to his promise―He went back on his word.
◆契約を履行する to keep to one's agreement―abide by one's agreement