illisible

Illisible is commonly encountered as a misspelling or as a word in non-English texts. In English, the standard adjective is illegible, meaning not readable due to unclear handwriting, poor print quality, or insufficient contrast between text and background.

Etymology and language notes

Illegible derives from Latin illegibilis, formed with the negative prefix in- attached to legibilis, meaning readable. The form illisible exists in French, where illisible means unreadable, and is sometimes seen in English-language texts when quoting or referring to French material. In English, however, illisible is generally considered erroneous or at least nonstandard.

Usage and examples

In English prose, use illegible to describe text that cannot be read: The note was illegible after the coffee spill. When writing about French text, you would use illisible in a French sentence (Le document est illisible) but would typically translate or adjust to readable/unreadable in English when appropriate. English readers may encounter illisible only in quotations or as a direct reference to the French word.

Causes of illegibility

Common causes include poor handwriting, small or crowded type, low contrast, aged or damaged documents, and scanning or OCR errors. Addressing these factors—clear handwriting, larger or higher-contrast fonts, and careful proofreading—improves legibility and readability.

See also

Legibility, illegibility, readability, typography.