Difference between 'oxymoron', 'paradox', 'contradiction' and 'misnomer' [closed]

What is the difference between the words oxymoron, paradox, contradiction and misnomer? For example,

Benevolent dictator is an oxymoron.

If I replace oxymoron with misnomer, paradox, or contradiction, how will the meaning change?

  1. Paradox

A seemingly absurd or contradictory statement or proposition which, when investigated, may prove to be well-founded or true.

The uncertainty principle leads to all sorts of paradoxes, like particles being in two places at once.
Oxford Dictionaries

  1. Misnomer

A wrong or inaccurate name or designation.

‘King crab’ is a misnomer -— these creatures are not crustaceans at all.
Oxford Dictionaries

A wrong or inaccurate use of a name or term.

To call this ‘neighbourhood policing’ would be a misnomer.

  1. Oxymoron

A figure of speech in which apparently contradictory terms appear in conjunction.

Faith unfaithful kept him falsely true.
Oxford Dictionaries

  1. Contradiction

Combination of statements, ideas, or features which are opposed to one another.

The proposed new system suffers from a set of internal contradictions.

A situation in which inconsistent elements are present.

The paradox of using force to overcome force is a real contradiction.

The statement of a position opposite to one already made.

The second sentence appears to be in flat contradiction to the first.
Oxford Dictionaries

All of them seem the same to me.


Solution 1:

A paradox is a logical issue, where a conclusion and the reasoning that led to it are in conflict - "I always lie" for example.

A misnomer is a labelling issue. It is a name that suggests something that is not true. Pencil lead, for example, is not lead but graphite, and catgut is not made from cats guts.

A contradiction is a constancy issue. It is saying two things that are not consistent. For example, if person A tells you that Jane is 23 years old, and person B says she is 33 years old, you have a contradiction.

An oxymoron is a word choice issue. It is a figurative construction using apparently contradictory words together. Crash landing is an example.

A crash landing is an oxymoron because a crash and a landing are two different things. The first could easily kill you and the second should not. It is not a contradiction because there is only one piece of of information. It is not a misnomer because nobody expects a crash landing to be gentle, though it could be if the crash landing was indeed very gentle. It is not a paradox because there is no chain of reasoning leading to a conflicting conclusion.