幕
まく · maku · JLPT N3 · noun
curtain
🎭 幕 = 莫 (sound) over 巾 (cloth): a hanging cloth, the stage curtain
The 巾 radical marks cloth and fabric, as in 帆 (sail) and 布 (cloth). A theatre curtain rises and falls between acts, so 幕 also counts acts: 第一幕 means Act One. 開幕 (かいまく) is the curtain opening, or the start of an event.
幕 — grass 艹 + sun 日 + big 大 + cloth 巾
Originally a semantic-phonetic compound: 莫 (mù, sunset/dusk) provides the sound and the idea of evening, while 巾 (cloth) gives the meaning. It depicted a cloth hung at dusk, hence 'curtain' or 'tent,' later extended to 'act/scene' in a play.