Antonyms for the phrase "giving consent" include denying, refusing, rejecting, opposing, defying, forbidding, and dissuading. Denying implies a negative response to a request, while refusing suggests a steadfast rejection of a proposal. Rejecting indicates a complete dismissal of an offer, while opposing exhibits active resistance. Defying connotes challenging or disobeying, while forbidding shows a prohibition of a certain action. Finally, dissuading implies actively persuading someone against giving consent. These antonyms offer a range of alternatives for expressing a lack of agreement or disagreement, giving individuals the ability to communicate with greater precision and specificity.