Extraneous mark

A mark on a paper ballot that appears to be unrelated to the act of indicating a voter’s selection. Examples include: a mark made unintentionally by a voter that is obviously not related to making a selection; a hesitation mark, a dot within or outside of the contest option position made by resting a pen or pencil on the ballot; written notes or identifying information not related to indication of the voter’s selection; or printing defects.

Source: Election Terminology Glossary - Draft, National Institute of Standards and Technology (NIST), https://pages.nist.gov/ElectionGlossary/