A printing defect characterized by a solid printed area ringed by a blank unprinted area, typically caused by an ink-receptive particle adhering to the surface of the printing plate, offset blanket, gravure cylinder, or other image-carrying surface. Sources of doughnut hickey-generating particles are bits of ink skin (called ink hickeys), dirt from the press, chips of flaking ceiling paint, or other various dust and debris that pick up ink, but as raised surfaces, do not allow the surrounding area to print. Doughnut hickeys are typically not caused by paper lint, which tends to produce void hickeys. Some lint can begin as a doughnut hickey and turn into a void hickey. (See Hickey.)
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