The phrase "says nothing doing" can be interpreted as a refusal or denial. Its antonyms, on the other hand, would imply agreement or acceptance. Some possible antonyms include "yes," "okay," "certainly," "absolutely," "definitely," "of course," "agreed," "all right," "willing," "gladly," and "surely." These words express a positive response or affirmation, as opposed to the negative and dismissive tone of "says nothing doing." In conversation, using antonyms of "says nothing doing" can avoid misunderstandings and ensure clear communication.