"Shot off mouth" is a colloquial term used to describe someone who talks too much, often without thinking first. While there are several synonyms for this phrase, such as "blabbermouth," "talkative," and "chatty," let us focus on its antonyms - words that convey the opposite meaning. Some examples of antonyms for "shot off mouth" might include "reserved," "introspective," "thoughtful," "taciturn," and "shy." People who possess these qualities tend to speak sparingly and thoughtfully, preferring to listen to others rather than dominating the conversation. Antonyms for "shot off mouth" can, therefore, be handy when describing individuals who are quiet, composed, and measured in their speech.