Terms indicating or emphasising negation - for example, any, at all, ever, neither.
A negative polarity item is an expression that is restricted to negative contexts and some other semantically related contexts such as questions and conditional clauses although its semantic properties would seem to allow occurrence in positive contexts as well.
Examples include indefinite pronouns such as any, either, minimizers such as a fig, a drop, a wink, and verbal idioms such as lift a finger, budge an inch.
Negative polarity items are attested in most languages.
