第一手
dì yī shoǔ · HSK 7
first-hand
☝️ dì yī shǒu = ordinal-#1 + hand — the first hand to touch it
第 marks sequence, 一 is one, 手 is hand. Together: the first hand on something, i.e. direct, unmediated experience. If your own hand was there, the info is first-hand.
第 — bamboo radical 竹 (⺮) + 弟 'younger brother'
Originally written with 弟, which depicted a cord wound in order around a stake — implying sequence or order. The bamboo radical 竹 was later added (because bamboo strips were used for numbered tallies and documents), giving 第 the meaning of ordinal number, sequence, or rank.
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.'
手 — pictograph of a hand with five fingers
手 is a pictograph showing an open hand with fingers and a wrist. Early bronze and oracle bone forms clearly depict five splayed fingers, which simplified over time into the modern shape. It keeps its original meaning of 'hand' and also serves as a radical in many characters related to hand actions.