A check; a relapse; a discouragement; a setback.
Whatever is thrown back in its course, such as water.
To plow again in the fall; said of prairie land broken up in the spring.
A denial or contradiction.
A proposition which is the contradictory of another proposition and which can be obtained from that other proposition by the appropriately placed addition/insertion of the word "not". (Or, in symbolic logic, by prepending that proposition with the symbol for the logical operator "not".)
The logical operation which obtains such (negated) propositions.
The act of negating something.