As a conclusion is a phrase that we often use to sum up or bring an end to something we are discussing or writing about. However, sometimes we might want to express a different tone or idea, which requires the use of antonyms. Some of the antonyms for as a conclusion include starting, beginning, initiating, opening, introducing, or commencing. Instead of ending a discussion or writing, these words suggest a shift towards the beginning or starting of something. Moreover, other antonyms could be "uncertainty," "ambiguity," or "vagueness," as these words suggest a lack of clarity about the subject matter. Ultimately, using antonyms can help us convey different meanings and evoke different emotions or responses to our readers or listeners.