The word "瓮声瓮气" is formed by taking the character "瓮" (meaning an earthen jar) and combining it with "声" (sound) to create "瓮声", literally "jar sound", and then repeating "瓮" with "气" (breath or vocal quality) to form "瓮气", with the entire compound describing a voice that is muffled and hollow, as if emanating from a jar.