着席
ちゃくせき · chakuseki · JLPT N1 · noun
down
着 — sheep 羊 (top) + eye 目 (bottom)
着 originated as a variant of 著, which depicted plants emerging visibly above ground (grass radical 艹 over 者). Over time 着 split off to carry meanings like 'attach,' 'wear,' or a verb suffix marking ongoing action (zhe), while 著 kept senses like 'manifest' or 'author.'
席 — 广 (shelter) + 巾 (cloth), over woven mat 苫
Originally a pictograph of a woven mat or rush mat used for sitting on the floor, with 巾 (cloth) hinting at the woven material under a shelter 广. Because guests were seated on such mats, 席 extended to mean 'seat,' 'place at a banquet,' and later any 'seat' or 'membership' in a group.