zona penumbrosa

(n.) = twilight zone

Ex. U denotes the umbra, ie those documents which are clearly relevant (within the shadow of the subject); P denotes the penumbra (the 'twilight zone'); and A denotes alien, ie those documents which are clearly not relevant.

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(n.) = twilight zone

Ex: U denotes the umbra, ie those documents which are clearly relevant (within the shadow of the subject); P denotes the penumbra (the 'twilight zone'); and A denotes alien, ie those documents which are clearly not relevant.