A riddle for your time (3)

This one is slightly harder then the previous two.

I'm not a pool, a tree, a slave, a website, or a shirt.

But all have something that is related to me.

What am I?

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I think there are many possible answers (anything other than pool, tree. slave. website and shirt can be the answer. – AeJey Jan 14 at 8:29
Yes, but probably only one relevant non-trivial answer... ;) – Baldrick Jan 14 at 8:29
I have updated the question using your hint. Hope it is ok for you. – AeJey Jan 14 at 8:30
Like i said, this one is slightly harder ;) In this case i think the hint actually needed to be part of the question so its fine by me @AeJey – Marco Geertsma Jan 14 at 8:42
Well actually, i dont think this riddle can result in only one answer, although i have a specific answer in mind the answer to this riddle may actually be different then the one i anticipated at first. – Marco Geertsma Jan 14 at 8:50

I think it's

Book

Explanation

Pool and book have cover
Tree and book have leaves
Slaves and books are bound
Website and book have pages
Shirt and book have sleeves.

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Haha right again ;) You sir are amazing at riddles. – Marco Geertsma Jan 14 at 9:14
Thank you @Macro Geertsma :) – AeJey Jan 14 at 9:24
Slaves and books are bound, not bounded. – Ypnypn Jan 15 at 2:36
have please, not has – Hanky Panky Jan 15 at 9:31
Thank you for pointing out the mistakes. Edited now. :) – AeJey Jan 15 at 10:15

maybe you are

a dog
- a tree has a bark
a slave has a master
a shirt has a collar
a pool can have a guard (ie guarddog)
... though i'm struggling with website...

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Nice try but not the right answer unfortunatly – Marco Geertsma Jan 14 at 8:47

maybe you are

Golf