You can deep-six something even if you are not a sailor.

即使不是水手，你也可以抛弃某物。

youdao

One language expert says that deep six is the bottom of the ocean.

VOA: special.2009.05.24

I mean, isn't it somewhat inefficient to load it really deep, because I assume if a spear is only six feet long, what are people in the back going to be doing?

我觉得,过于厚实的方阵会影响效率,据我所知,长矛也就六尺来长,那站在方阵后方的战士都在干什么呢

耶鲁公开课 - 古希腊历史简介课程节选

Thus,the deep six is the deepest fathom.

VOA: special.2009.05.24

Last month, they sent a letter to feisty CEO Jim Buckmaster asking him to deep six the section.

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He also tried to deep-six the Minnesota Twins, under the guise of weeding out weak franchises.

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Also, refer to No. 1 and stash your family photos on the refrigerator and deep-six the extensive pile of magazines in the restroom.

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