The term "most tenderfoot" is not frequently used in everyday language, but if we were to think of some antonyms - words that have the opposite meaning - we could consider "seasoned", "experienced", "skilled", "adroit", "adept", "expert", "accomplished", "proficient", "dexterous", or "masterful". These terms would describe someone who is not new or inexperienced and who has a high level of ability, knowledge, or expertise in a particular field or activity. Someone who is "most tenderfoot", on the other hand, would be considered a beginner, novice, or newcomer who lacks experience or skill.