The word 心旷神怡 is formed by combining two parallel phrases: 心旷, meaning "heart spacious" or "open-hearted", and 神怡, meaning "spirit joyful". Here, 心 (heart) and 神 (spirit) are nouns modified by the adjectives 旷 (spacious) and 怡 (joyful), respectively. The four characters are paired structurally to create a compound meaning where the ease of the heart and the delight of the spirit together convey a sense of total refreshment and contentment.