The characteristic or quality of being illegible; the quality of being difficult or impossible to read.(noun)
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Use "illegibility" in a sentence
"A kind of illegibility, though a different kind, stole over Mr"
"Complaints that "some of the writing of the Pusrawi doctor's report cannot be comprehended because of" illegibility "are hardly convincing, for doctors handwriting are noted for their sometimes illegible scrawl but that does not mean overall what he says cannot be understood!"
"Getting Upper: Graphic Designers and Artists Reconsider the Alphabet charges twenty-six designers with re-imagining a letter from the alphabet, using the illegibility and deconstructive nature of graffiti as their starting point."