The "hook" is a fish hook.

“钩”在这里指的是鱼钩。

youdao

A fish hook has a barb to prevent the fish from escaping after being hooked.

鱼钩上都有一个倒钩以防上了钩的鱼逃走。

youdao

The stomach contained a fish hook , bits of digested fish skull and some tapeworm.

胃里面有个钓鱼钩，少量消化之后残留的鱼骸和一些绦虫。

youdao

Jeff Peters and Andy Tucker were now ready to catch a few fish on the hook.

VOA: special.2010.04.24

Edison would go fishing in the middle of a workday at a nearby pond, and he would fish with a baitless hook.

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It took me four hours to hook a fish and 40 minutes to reel him in.

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In March he will likely head to fish the saltwater flats in Florida for bonefish and tarpon and perhaps permit (a species of fish that has thus far eluded his hook).

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