Being at daggers with means being in a state of extreme hostility or conflict with someone. The antonyms for this phrase include words like harmonious, peaceful, cordial, friendly, agreeable, and amicable. If you are in a harmonious relationship with someone, it means you are on good terms and share a positive bond. When things are peaceful, there is no hostility or tension, and things are running smoothly. A cordial relationship implies warm and friendly interactions. If you are friendly with someone, you have a pleasant and courteous relationship. Agreeable and amicable both signify an absence of conflict or ill feelings towards another person.