In the dictionary, *position* as a verb means "to determine the position of or locate". 

1. What word would represent the adjectival form of *position*? and what would its meaning be?
2. Is it acceptable grammatically for a verb to be put before a noun - eg a **positioning** device - to describing a device used to determine the position or location of something (eg It is a positioning device that locates optimal treatment sites). If this is proper grammatically can you please elaborate on which grammatical rules are at work here that allow this?