The word 高兴 is formed through a conceptual blend where the first character 高 ("high, tall") and the second character 兴 ("to rise, to flourish") are fused not literally, but metaphorically. It visually synthesizes the image of something physically elevated with the dynamic sense of an upward surge or blooming, creating a new, unified idea of an inner state that is "raised up" or "lifted", effectively picturing the feeling of joy as a heart or spirit that is high and rising.