[Sopater]

When I read the passages, all of the English ones specifically use the word "tail".

The Hebrew word which was translated as "tail" is זנב (zânâb ).

Strong's dictionary says: the tail (literally or figuratively): - tail.

Brown-Driver-Briggs’ Hebrew Definitions says: tail, end, stump

If you're seeing a reference a specific appendage other than a tail that might belong to a hippo, elephant or rhino, it's because you want it to be that appendage. Shame on you. ;-)

[ColdWater]

Every passage you quoted refers to the non-tail appendage. Open your eyes.

[ColdWater]

Read the passages. 16 is referring to his loins, 17 is referring to his loins. The meaning of ‘tail’ is obvious.

15 “Look at the behemoth, [a]
which I made along with you
and which feeds on grass like an ox.

16 What strength he has in his loins,
what power in the muscles of his belly!

17 His tail [b] sways like a cedar;
the sinews of his thighs are close-knit.