质子 Traditional form: 質子 Pinyin (reading): zhìzǐ Definitions: proton (positively charged nuclear particle) a prince sent to be held as a hostage in a neighbouring state in ancient China Characters: 质 - essence, nature; material, substance 子 - son, child; seed, egg; fruit; small thing Traditional characters: 質 - essence, nature; material, substance 子 - son, child; seed, egg; fruit; small thing