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beginning; start; outset; opening
first (in line, etc.)
origin
such as ...; not to mention ...
「初め」 has another reading with different meanings.
初めのうちは緊張していた。
I was nervous at the beginning.
初めに説明しますね。
I'll explain first.
この本は初めから読んだほうがいいよ。
You should read this book from the beginning.