The word "most uncompanionable" can be defined as someone who is unfriendly, unsociable, or difficult to get along with. In contrast, the antonyms for this phrase would be "kind, friendly, sociable, amiable, convivial, approachable," and "warm-hearted." These terms refer to individuals who enjoy being around others and are welcoming and gracious in social situations. They often possess excellent interpersonal skills and have a positive outlook on life, making them enjoyable company for others. In conclusion, the opposite of "most uncompanionable" are individuals who are outgoing, cheerful, and easy-going.