Inky stain (4)

I believe the answer is:

blot

(Other definitions for blot that I've seen before include "Don't do it to your copybook" , "Stain left by spilled ink" , "bad mark" , "Stain (on landscape?)" , "Dry piece of writing" .)

I've seen this clue in the Penny Press, the Newsday.com, the King Feature Syndicate, the LA Times and the Family Time.

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