Excerpt: "‘Paradox’ is derived from two words that literally mean against opinion. The Oxford English Dictionary (1989; vol. 11, p. 185) identifies several meanings for ‘paradox’. It may refer to: (1) claims contrary to common opinion, often suggesting that the statement is incredible, absurd or fantastic, but sometimes with a favourable connotation as a correction for ignorance; (2) a statement that seems self-contradictory, but which is actually well founded; (3) a statement that involves a genuine *contradiction; (4) in *logic, a conclusion based on acceptable premises and sound *reasoning that nonetheless is self-contradictory. These inconsistent uses of the term pose practical problems for communication, as the intended meaning may not always be apparent."
Bufford, Rodger K., "Paradox" (2006). Faculty Publications - Grad School of Clinical Psychology. 305.