The word "most sanctioning" refers to the act of officially approving or authorizing something. However, there are several antonyms that denote a lack of approval or disapproval. These antonyms include: prohibit, ban, veto, disapprove, oppose, reject, unauthorize, outlaw, condemn, and restrict. These words represent a range of negative attitudes towards something or someone, indicating disfavor or disapproval. Depending on the context, using these antonyms in place of "most sanctioning" can shift the tone of a sentence entirely, and convey a different meaning. It is important to choose the correct word in order to accurately represent the intended sentiment.