Curmudgeonly is an adjective that describes a person who is ill-tempered or grumpy. The word suggests a miserable, pessimistic, and stubborn individual who is not easy to please. On the other hand, antonyms for the word curmudgeonly would be words that suggest cheerful, optimistic, and easy-going personalities. Words like genial, affable, amiable, and cordial convey friendly and approachable personalities that are always ready to engage in a conversation. Other antonyms that could fit this description include easygoing, cheerful, and pleasant. All of these adjectives suggest a person who is in a good mood and happy to engage with the world around them.