nonentity vs nothing

nonentity

• an unimportant or insignificant person 

• the state of not existing; nonexistence 

nothing

• A nobody (insignificant person). 

• Something trifling, or of no consequence or importance. 

• A trivial remark especially in the term sweet nothings. 

• Not any thing; no thing. 

• An absence of anything, including empty space, brightness, darkness, matter, or a vacuum.