Is there a way to hid a note or archive it so that it isn't "in my face" in Evernote?
I have some reference notes, that I don't need to see all the time, but I still want them accessible via Evernote.
No there is no simple built-in function for this.
But there are multiple ways around it.
You could make a notebook 'Archive', where you move notes into.
You could tag "archived" notes with a tag 'Archive' and then whenever you search, use "-tag:Archive".
EDIT: If you want the contents of the note to not be visible in the 'Notes by'/'All Notes' section, then you can encrypt them.