"Out of Reach" is a/an:

Out of reach
- It is an idiom.
- It means not able to be achieved or  at a distance at which someone or something cannot be touched or grasped.
- Its not clause. Because it does not have a subject+verb combination. So its a Phrase. 
Ex: Their goal is out of reach.


A phrase is one or more words that form a meaningful grammatical unit within a clause. (Not a complete sentence though)

দুই বা ততোধিক শব্দ মিলিয়ে সেই শব্দগুচ্ছটি যখন একটি নির্দিষ্ট  Parts of Speech এর অর্থ প্রকাশ করে, তখন তাকে Phrase বলে

Source: Merriam-Webster Dictionary