noun.
A person who adheres to the philosophy of existentialism.
adjective.
Of or pertaining to existentialism.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
noun.
a philosopher who emphasizes freedom of choice and personal responsibility but who regards human existence in a hostile universe as unexplainable
adjective.
relating to or involving existentialism
Word Usage
"In all other things than atheism, now, I suspect the word existentialist fits me best- though the better read may correct me."