What word describes a mood that is characterized by being cheerful and playful?

The word that best describes a mood characterized by being cheerful and playful is "jocular." This term specifically relates to a lighthearted, humorous, and playful attitude, often associated with laughter and joy. When someone is described as jocular, it suggests they have a friendly and fun disposition, engaging others in a way that spreads happiness and amusement.

In contrast, "morose" denotes a gloomy or sullen atmosphere, which is the opposite of cheerfulness. "Gregarious" refers to someone who enjoys the company of others and is sociable, but it does not inherently imply playfulness. "Peevish" describes a mood that is irritable or easily annoyed, which certainly contrasts with being cheerful. Therefore, "jocular" is the most fitting choice for a mood that emphasizes cheerfulness and playfulness.