Disacknowledge means to refuse to recognize or accept something, or to deny the existence of something. There are several synonyms for this word, including reject, disavow, repudiate, negate, refute, and renounce. Reject involves refusing to accept something, while disavow refers to denying responsibility for something. Repudiate means to refuse to accept or acknowledge something as true or valid. Negate involves making something null and void, and refute refers to proving something to be false. Renounce means to give up or reject a claim or belief. These synonyms can be used interchangeably depending on the context and intended meaning.