punctum delens

Etymology
.

Noun

 * 1)  A dot placed above a letter to indicate that it is a copying error and should be ignored.
 * 2)  A dot placed above a consonant in Irish, when it is written in Gaelic script, to indicate that the consonant is lenited.

Etymology
From +, present active participle of.

Noun

 * 1)  a punctum delens; mark made to indicate that a written character is an error to be ignored.