清真寺 (read: Qīngzhēnsì)
is the writing that almost always be seen at every gate of muslim worship building which I visited in China. At Niujie mosque in Beijing, Dalian mosque in Dalian, Tanggu mosque in Tianjin, and Dongsi mosque in Beijing. It literally means mosque, but my Chinese friend always said that is Muslim temple.
So then, I tried to figure out the basic words that formed it by breaking it down. First word 清 means “clear”. Second word 真 means “true”. Third word 寺 means “temple” or “place of worship”. The first and second words can be combined as 清真 which is means “halal” or “muslim”, or can be combined as 真清 which means “really clear”. Presumedly the word is first mentioned when the Chinese people see the Muslims have a rule to only eat halal food, clearly permissible, not doubtful or which is still not clear and even unlawful or prohibited.