【2021-03-20】

forenoon这个词在1940年前还挺常用的，后来逐渐消失，被词义扩大的morning挤掉了，另外，evening 和 night 的区别好像也模糊了？

有人在stackexchange上 给出了一个说法 ，好像挺有道理： More broadly than the other answers, forenoon is one of the time-of-day terms that has become much less commonly used over the last century or so, possibly as a result of the widespread use of artificial lighting. In earlier times, it was common to see the day divided into much more specific segments, but now only the terms in bold are in common usage for describing the time of day: dawn

twilight (morning)

sunrise

morning

forenoon

midday

afternoon

evening

sunset

twilight (evening)

dusk

night As a fan of the Aubrey–Maturin series, set in the early 1800s, I'm quite familiar with the nautical term "forenoon watch", but I can't ever recall having seen "forenoon" used in a modern setting. @ybfelix:用电灯来解释需要更多证据。我来猜测的话，会猜是手表等计时工具的逐渐铺开，需要精确报时的场合可以直接说几点钟（同时12时制只强调AM与PM的区分，所以它生存下来了

@whigzhou: 嗯，钟表肯定起了作用，另外，室外活动的减少，严格化的作息制度，对时间用词可能都有影响