Theoretical limits of CCK (Field API) unlimited Multi Value Field - 170 000 values I plan to have a large multi value field, in my case a node reference field, around 170 000 values.

I guess on node view I can hide the field, and just put in a Views block so the node can be viewed. Editing the node manually will be impossible, as the multi value fields have no paging and Drupal would just load the entire 170 000 values onto the screen. Any tips on solving this?

What I plan on having this is a content type "list" and a content type "item". In the items I will load an dictionary word lists, and in the "list" content type I will group them in different lists. I could use taxonomy as well, but nodes have a better permission control.
No chance, hiding doesn't help, drupal will still load all values even if the field is hidden. 

You could add the reference field on the item type and then load them through a view. 

Or use the relation project, but it's ui might break too.