Second Hand
noun
The second needle is the thin hand that indicates seconds on your clock. That's the second hand of a clock.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
ねむれなかったので、時計の秒針を見て夜を過ごしました。
I couldn't sleep, so I spent the night watching the second hand of the clock.
秒針のチクタクチクタクいう音がうるさくてイライラする。
The ticking sound of the second hand is so loud and annoying, it's frustrating.
腕時計の秒針が折れちゃってるの。
My wrist watch's second hand has been broken.