一体
yītǐ · HSK 7
all concerned
一 (one) + 体 (body) = one body, i.e. everything fused into a single integral whole
一 — single horizontal stroke
一 is one of the simplest pictographs in Chinese, depicting a single horizontal line to represent the number one. It has retained essentially the same form since oracle bone script over 3,000 years ago. By extension it also means 'first,' 'whole,' or 'same.'