区切り
くぎり · kugiri · JLPT N1 · noun
end
🛑 区 = section + 切り = cut: a cut that divides text into sections is a stop
区 means division or section, and 切り means cutting. A 区切り is the point where a flow of text or time is cut into parts, so it means an end, a stop, or punctuation.
区 — enclosure 匚 + 品 (items)
Originally a pictograph of items (品) hidden inside a container (匚), meaning to store or conceal. The sense extended to a bounded space, then to an administrative district or area. As a surname read Ōu, it preserves the older 'hidden/enclosed' nuance.
切 — 七 (phonetic) + 刀 (knife radical)
切 is a semantic-phonetic compound: 刀 'knife' gives the meaning of cutting, while 七 supplies the sound. The original sense was to slice or cut with a blade. From there it extended figuratively to 'close to' (as in pressed against) and 'urgent/earnest', as in 切实.