I read a novel earlier this year entitled Elixir Bound, a YA fantasy about a quest to obtain the ingredients for a healing elixir. (It's a very good book by the way.) The title got me thinking about the word bound, which is a strange word because it has so many meanings and some of these meanings are contradictory. This is a relatively common occurrence in English which draws words from so many other languages. Words that have contradictory meanings depending on their context are called contronyms. In the case of bound, it can mean you're going somewhere or restrained from moving.
The restrained version of bound is the past tense of bind, which derives from Old English bindan, meaning to tie with bonds or make captive. The past participle of bindan is bunden. The Old English word likely comes from the Proto-Germanic word *bindan. Variations on Old English bindan with similar spelling and meaning exist in Old Saxon, Old Norse, Old Frisian, Old High German, German, and Gothic.
There's another wrinkle in the restrictive meanings of bound. The noun bound meaning a limit or boundary (think out of bounds) derives from the Anglo-Latin term bunda, which comes from Old French bonde, a variant of bodne that derives from Medieval Latin bodina.
For the ready to go meaning of bound, we start with the Middle English boun, which derives from Old Norse buinn, meaning to dwell or prepare. The Old Norse word derives from the Proto-Germanic *bowan. Similar words exist in Old High German and Old Danish.
So, what does “bound” mean in Katie Carroll's Elixir Bound? That's the brilliant part. Carroll packs both meanings into her title. The protagonist Katora is going on a quest to secure the ingredients for the elixir. She's bound for the mountain on which a particular plant grows. However, once Katora finds it and agrees to be the elixir's guardian, she becomes bound to it. She cannot give up her guardianship of her own free will.